diff --git a/media/libaaudio/examples/utils/AAudioArgsParser.h b/media/libaaudio/examples/utils/AAudioArgsParser.h
index ada37e2..142b295 100644
--- a/media/libaaudio/examples/utils/AAudioArgsParser.h
+++ b/media/libaaudio/examples/utils/AAudioArgsParser.h
@@ -17,6 +17,8 @@
 #ifndef AAUDIO_EXAMPLE_ARGS_PARSER_H
 #define AAUDIO_EXAMPLE_ARGS_PARSER_H
 
+#define MAX_CHANNELS                     8
+
 #include <cctype>
 #include <unistd.h>
 #include <stdio.h>
@@ -39,6 +41,10 @@
     }
 
     void setChannelCount(int32_t channelCount) {
+        if (channelCount > MAX_CHANNELS) {
+            printf("Sorry, MAX of %d channels!\n", MAX_CHANNELS);
+            channelCount = MAX_CHANNELS;
+        }
         mChannelCount = channelCount;
     }
 
diff --git a/media/libaaudio/examples/utils/AAudioSimplePlayer.h b/media/libaaudio/examples/utils/AAudioSimplePlayer.h
index 606c4ba..1061e42 100644
--- a/media/libaaudio/examples/utils/AAudioSimplePlayer.h
+++ b/media/libaaudio/examples/utils/AAudioSimplePlayer.h
@@ -19,11 +19,10 @@
 #ifndef AAUDIO_SIMPLE_PLAYER_H
 #define AAUDIO_SIMPLE_PLAYER_H
 
-#include <unistd.h>
 #include <sched.h>
+#include <unistd.h>
 
 #include <aaudio/AAudio.h>
-#include <atomic>
 #include "AAudioArgsParser.h"
 #include "SineGenerator.h"
 
@@ -36,7 +35,7 @@
 // How long to sleep in a callback to cause an intentional glitch. For testing.
 #define FORCED_UNDERRUN_SLEEP_MICROS     (10 * 1000)
 
-#define MAX_TIMESTAMPS   16
+#define MAX_TIMESTAMPS                   16
 
 typedef struct Timestamp {
     int64_t position;
@@ -70,13 +69,6 @@
     }
 
     // TODO Extract a common base class for record and playback.
-    /**
-     * Also known as "sample rate"
-     * Only call this after open() has been called.
-     */
-    int32_t getFramesPerSecond() const {
-        return getSampleRate(); // alias
-    }
 
     /**
      * Only call this after open() has been called.
@@ -172,6 +164,7 @@
         result = AAudioStreamBuilder_openStream(builder, &mStream);
 
         AAudioStreamBuilder_delete(builder);
+
         return result;
     }
 
@@ -212,13 +205,35 @@
         aaudio_result_t result = AAudioStream_requestStop(mStream);
         if (result != AAUDIO_OK) {
             printf("ERROR - AAudioStream_requestStop() returned %d %s\n",
-                    result, AAudio_convertResultToText(result));
+                   result, AAudio_convertResultToText(result));
         }
         int32_t xRunCount = AAudioStream_getXRunCount(mStream);
         printf("AAudioStream_getXRunCount %d\n", xRunCount);
         return result;
     }
 
+    // Pause the stream. AAudio will stop calling your callback function.
+    aaudio_result_t pause() {
+        aaudio_result_t result = AAudioStream_requestPause(mStream);
+        if (result != AAUDIO_OK) {
+            printf("ERROR - AAudioStream_requestPause() returned %d %s\n",
+                   result, AAudio_convertResultToText(result));
+        }
+        int32_t xRunCount = AAudioStream_getXRunCount(mStream);
+        printf("AAudioStream_getXRunCount %d\n", xRunCount);
+        return result;
+    }
+
+    // Flush the stream. AAudio will stop calling your callback function.
+    aaudio_result_t flush() {
+        aaudio_result_t result = AAudioStream_requestFlush(mStream);
+        if (result != AAUDIO_OK) {
+            printf("ERROR - AAudioStream_requestFlush() returned %d %s\n",
+                   result, AAudio_convertResultToText(result));
+        }
+        return result;
+    }
+
     AAudioStream *getStream() const {
         return mStream;
     }
@@ -232,23 +247,49 @@
 
 typedef struct SineThreadedData_s {
 
-    SineGenerator  sineOsc1;
-    SineGenerator  sineOsc2;
-    Timestamp      timestamps[MAX_TIMESTAMPS];
-    int64_t        framesTotal = 0;
-    int64_t        nextFrameToGlitch = FORCED_UNDERRUN_PERIOD_FRAMES;
-    int32_t        minNumFrames = INT32_MAX;
-    int32_t        maxNumFrames = 0;
-    int32_t        timestampCount = 0; // in timestamps
+    SineGenerator      sineOscillators[MAX_CHANNELS];
+    Timestamp          timestamps[MAX_TIMESTAMPS];
+    int64_t            framesTotal = 0;
+    int64_t            nextFrameToGlitch = FORCED_UNDERRUN_PERIOD_FRAMES;
+    int32_t            minNumFrames = INT32_MAX;
+    int32_t            maxNumFrames = 0;
+    int32_t            timestampCount = 0; // in timestamps
+    int32_t            sampleRate = 48000;
+    int32_t            prefixToneFrames = 0;
+    bool               sweepSetup = false;
 
-    int            scheduler = 0;
-    bool           schedulerChecked = false;
-    bool           forceUnderruns = false;
+    int                scheduler = 0;
+    bool               schedulerChecked = false;
+    bool               forceUnderruns = false;
 
     AAudioSimplePlayer simplePlayer;
     int32_t            callbackCount = 0;
     WakeUp             waker{AAUDIO_OK};
 
+    /**
+     * Set sampleRate first.
+     */
+    void setupSineBlip() {
+        for (int i = 0; i < MAX_CHANNELS; ++i) {
+            double centerFrequency = 880.0 * (i + 2);
+            sineOscillators[i].setup(centerFrequency, sampleRate);
+            sineOscillators[i].setSweep(centerFrequency, centerFrequency, 0.0);
+        }
+    }
+
+    void setupSineSweeps() {
+        for (int i = 0; i < MAX_CHANNELS; ++i) {
+            double centerFrequency = 220.0 * (i + 2);
+            sineOscillators[i].setup(centerFrequency, sampleRate);
+            double minFrequency = centerFrequency * 2.0 / 3.0;
+            // Change range slightly so they will go out of phase.
+            double maxFrequency = centerFrequency * 3.0 / 2.0;
+            double sweepSeconds = 5.0 + i;
+            sineOscillators[i].setSweep(minFrequency, maxFrequency, sweepSeconds);
+        }
+        sweepSetup = true;
+    }
+
 } SineThreadedData_t;
 
 // Callback function that fills the audio output buffer.
@@ -265,9 +306,11 @@
         return AAUDIO_CALLBACK_RESULT_STOP;
     }
     SineThreadedData_t *sineData = (SineThreadedData_t *) userData;
-    sineData->callbackCount++;
 
-    sineData->framesTotal += numFrames;
+    // Play an initial high tone so we can tell whether the beginning was truncated.
+    if (!sineData->sweepSetup && sineData->framesTotal >= sineData->prefixToneFrames) {
+        sineData->setupSineSweeps();
+    }
 
     if (sineData->forceUnderruns) {
         if (sineData->framesTotal > sineData->nextFrameToGlitch) {
@@ -301,33 +344,32 @@
     }
 
     int32_t samplesPerFrame = AAudioStream_getChannelCount(stream);
-    // This code only plays on the first one or two channels.
-    // TODO Support arbitrary number of channels.
+
+
+    int numActiveOscilators = (samplesPerFrame > MAX_CHANNELS) ? MAX_CHANNELS : samplesPerFrame;
     switch (AAudioStream_getFormat(stream)) {
         case AAUDIO_FORMAT_PCM_I16: {
             int16_t *audioBuffer = (int16_t *) audioData;
-            // Render sine waves as shorts to first channel.
-            sineData->sineOsc1.render(&audioBuffer[0], samplesPerFrame, numFrames);
-            // Render sine waves to second channel if there is one.
-            if (samplesPerFrame > 1) {
-                sineData->sineOsc2.render(&audioBuffer[1], samplesPerFrame, numFrames);
+            for (int i = 0; i < numActiveOscilators; ++i) {
+                sineData->sineOscillators[i].render(&audioBuffer[i], samplesPerFrame,
+                                                    numFrames);
             }
         }
-        break;
+            break;
         case AAUDIO_FORMAT_PCM_FLOAT: {
             float *audioBuffer = (float *) audioData;
-            // Render sine waves as floats to first channel.
-            sineData->sineOsc1.render(&audioBuffer[0], samplesPerFrame, numFrames);
-            // Render sine waves to second channel if there is one.
-            if (samplesPerFrame > 1) {
-                sineData->sineOsc2.render(&audioBuffer[1], samplesPerFrame, numFrames);
+            for (int i = 0; i < numActiveOscilators; ++i) {
+                sineData->sineOscillators[i].render(&audioBuffer[i], samplesPerFrame,
+                                                    numFrames);
             }
         }
-        break;
+            break;
         default:
             return AAUDIO_CALLBACK_RESULT_STOP;
     }
 
+    sineData->callbackCount++;
+    sineData->framesTotal += numFrames;
     return AAUDIO_CALLBACK_RESULT_CONTINUE;
 }
 
diff --git a/media/libaaudio/examples/utils/SineGenerator.h b/media/libaaudio/examples/utils/SineGenerator.h
index a755582..9e6d46d 100644
--- a/media/libaaudio/examples/utils/SineGenerator.h
+++ b/media/libaaudio/examples/utils/SineGenerator.h
@@ -31,20 +31,20 @@
     }
 
     void setSweep(double frequencyLow, double frequencyHigh, double seconds) {
-        mPhaseIncrementLow = frequencyLow * M_PI * 2 / mFrameRate;
-        mPhaseIncrementHigh = frequencyHigh * M_PI * 2 / mFrameRate;
-
-        double numFrames = seconds * mFrameRate;
-        mUpScaler = pow((frequencyHigh / frequencyLow), (1.0 / numFrames));
-        mDownScaler = 1.0 / mUpScaler;
-        mGoingUp = true;
-        mSweeping = true;
+        mSweeping = seconds > 0.0;
+        if (mSweeping) {
+            mPhaseIncrementLow = frequencyLow * M_PI * 2 / mFrameRate;
+            mPhaseIncrementHigh = frequencyHigh * M_PI * 2 / mFrameRate;
+            double numFrames = seconds * mFrameRate;
+            mUpScaler = pow((frequencyHigh / frequencyLow), (1.0 / numFrames));
+            mDownScaler = 1.0 / mUpScaler;
+        }
     }
 
     void render(int16_t *buffer, int32_t channelStride, int32_t numFrames) {
         int sampleIndex = 0;
         for (int i = 0; i < numFrames; i++) {
-            buffer[sampleIndex] = (int16_t) (32767 * sin(mPhase) * mAmplitude);
+            buffer[sampleIndex] = (int16_t) (INT16_MAX * sin(mPhase) * mAmplitude);
             sampleIndex += channelStride;
             advancePhase();
         }
@@ -61,6 +61,7 @@
     void setAmplitude(double amplitude) {
         mAmplitude = amplitude;
     }
+
     double getAmplitude() const {
         return mAmplitude;
     }
diff --git a/media/libaaudio/examples/write_sine/src/write_sine.cpp b/media/libaaudio/examples/write_sine/src/write_sine.cpp
index 677fb6c..65d98d1 100644
--- a/media/libaaudio/examples/write_sine/src/write_sine.cpp
+++ b/media/libaaudio/examples/write_sine/src/write_sine.cpp
@@ -48,6 +48,7 @@
     int32_t  framesToPlay = 0;
     int32_t  framesLeft = 0;
     int32_t  xRunCount = 0;
+    int      numActiveOscilators = 0;
     float   *floatData = nullptr;
     int16_t *shortData = nullptr;
 
@@ -77,8 +78,8 @@
     actualSampleRate = AAudioStream_getSampleRate(aaudioStream);
     actualDataFormat = AAudioStream_getFormat(aaudioStream);
 
-    myData.sineOsc1.setup(440.0, actualSampleRate);
-    myData.sineOsc2.setup(660.0, actualSampleRate);
+    myData.sampleRate = actualSampleRate;
+    myData.setupSineSweeps();
 
     // Some DMA might use very short bursts of 16 frames. We don't need to write such small
     // buffers. But it helps to use a multiple of the burst size for predictable scheduling.
@@ -117,19 +118,18 @@
     // Play for a while.
     framesToPlay = actualSampleRate * argParser.getDurationSeconds();
     framesLeft = framesToPlay;
+    numActiveOscilators = (actualChannelCount > MAX_CHANNELS) ? MAX_CHANNELS : actualChannelCount;
     while (framesLeft > 0) {
-
+        // Render as FLOAT or PCM
         if (actualDataFormat == AAUDIO_FORMAT_PCM_FLOAT) {
-            // Render sine waves to left and right channels.
-            myData.sineOsc1.render(&floatData[0], actualChannelCount, framesPerWrite);
-            if (actualChannelCount > 1) {
-                myData.sineOsc2.render(&floatData[1], actualChannelCount, framesPerWrite);
+            for (int i = 0; i < numActiveOscilators; ++i) {
+                myData.sineOscillators[i].render(&floatData[i], actualChannelCount,
+                                                  framesPerWrite);
             }
         } else if (actualDataFormat == AAUDIO_FORMAT_PCM_I16) {
-            // Render sine waves to left and right channels.
-            myData.sineOsc1.render(&shortData[0], actualChannelCount, framesPerWrite);
-            if (actualChannelCount > 1) {
-                myData.sineOsc2.render(&shortData[1], actualChannelCount, framesPerWrite);
+            for (int i = 0; i < numActiveOscilators; ++i) {
+                myData.sineOscillators[i].render(&shortData[i], actualChannelCount,
+                                                  framesPerWrite);
             }
         }
 
diff --git a/media/libaaudio/examples/write_sine/src/write_sine_callback.cpp b/media/libaaudio/examples/write_sine/src/write_sine_callback.cpp
index 4f9cde6..c2dd7af 100644
--- a/media/libaaudio/examples/write_sine/src/write_sine_callback.cpp
+++ b/media/libaaudio/examples/write_sine/src/write_sine_callback.cpp
@@ -28,7 +28,6 @@
 #include <aaudio/AAudio.h>
 #include "AAudioExampleUtils.h"
 #include "AAudioSimplePlayer.h"
-#include "../../utils/AAudioSimplePlayer.h"
 
 /**
  * Open stream, play some sine waves, then close the stream.
@@ -36,37 +35,39 @@
  * @param argParser
  * @return AAUDIO_OK or negative error code
  */
-static aaudio_result_t testOpenPlayClose(AAudioArgsParser &argParser)
+static aaudio_result_t testOpenPlayClose(AAudioArgsParser &argParser,
+                                         int32_t loopCount,
+                                         int32_t prefixToneMsec)
 {
     SineThreadedData_t myData;
     AAudioSimplePlayer &player = myData.simplePlayer;
     aaudio_result_t    result = AAUDIO_OK;
     bool               disconnected = false;
+    bool               bailOut = false;
     int64_t            startedAtNanos;
 
     printf("----------------------- run complete test --------------------------\n");
     myData.schedulerChecked = false;
     myData.callbackCount = 0;
+    // TODO add a command line option for the forceUnderruns
     myData.forceUnderruns = false; // set true to test AAudioStream_getXRunCount()
 
     result = player.open(argParser,
                          SimplePlayerDataCallbackProc, SimplePlayerErrorCallbackProc, &myData);
     if (result != AAUDIO_OK) {
-        fprintf(stderr, "ERROR -  player.open() returned %d\n", result);
+        fprintf(stderr, "ERROR -  player.open() returned %s\n",
+                AAudio_convertResultToText(result));
         goto error;
     }
 
     argParser.compareWithStream(player.getStream());
 
-    // Setup sine wave generators.
-    {
-        int32_t actualSampleRate = player.getSampleRate();
-        myData.sineOsc1.setup(440.0, actualSampleRate);
-        myData.sineOsc1.setSweep(300.0, 600.0, 5.0);
-        myData.sineOsc1.setAmplitude(0.2);
-        myData.sineOsc2.setup(660.0, actualSampleRate);
-        myData.sineOsc2.setSweep(350.0, 900.0, 7.0);
-        myData.sineOsc2.setAmplitude(0.2);
+    myData.sampleRate = player.getSampleRate();
+    myData.prefixToneFrames = prefixToneMsec * myData.sampleRate / 1000;
+    if (myData.prefixToneFrames > 0) {
+        myData.setupSineBlip();
+    } else {
+        myData.setupSineSweeps();
     }
 
 #if 0
@@ -78,42 +79,93 @@
     }
 #endif
 
-    result = player.start();
-    if (result != AAUDIO_OK) {
-        fprintf(stderr, "ERROR - player.start() returned %d\n", result);
-        goto error;
-    }
+    for (int loopIndex = 0; loopIndex < loopCount; loopIndex++) {
+        // Only play data on every other loop so we can hear if there is stale data.
+        double amplitude;
+        int32_t durationSeconds;
+        if ((loopIndex & 1) == 0) {
+            printf("--------------- SINE ------\n");
+            amplitude = 0.2;
+            durationSeconds = argParser.getDurationSeconds();
+        } else {
+            printf("--------------- QUIET -----\n");
+            amplitude = 0.0;
+            durationSeconds = 2; // just wait briefly when quiet
+        }
+        for (int i = 0; i < MAX_CHANNELS; ++i) {
+            myData.sineOscillators[i].setAmplitude(amplitude);
+        }
 
-    // Play a sine wave in the background.
-    printf("Sleep for %d seconds while audio plays in a callback thread.\n",
-           argParser.getDurationSeconds());
-    startedAtNanos = getNanoseconds(CLOCK_MONOTONIC);
-    for (int second = 0; second < argParser.getDurationSeconds(); second++)
-    {
-        // Sleep a while. Wake up early if there is an error, for example a DISCONNECT.
-        long ret = myData.waker.wait(AAUDIO_OK, NANOS_PER_SECOND);
-        int64_t millis = (getNanoseconds(CLOCK_MONOTONIC) - startedAtNanos) / NANOS_PER_MILLISECOND;
-        result = myData.waker.get();
-        printf("wait() returns %ld, aaudio_result = %d, at %6d millis"
-               ", second = %d, framesWritten = %8d, underruns = %d\n",
-               ret, result, (int) millis,
-               second,
-               (int) AAudioStream_getFramesWritten(player.getStream()),
-               (int) AAudioStream_getXRunCount(player.getStream()));
+        result = player.start();
         if (result != AAUDIO_OK) {
-            if (result == AAUDIO_ERROR_DISCONNECTED) {
-                disconnected = true;
+            fprintf(stderr, "ERROR - player.start() returned %d\n", result);
+            goto error;
+        }
+
+        // Play a sine wave in the background.
+        printf("Sleep for %d seconds while audio plays in a callback thread. %d of %d\n",
+               argParser.getDurationSeconds(), (loopIndex + 1), loopCount);
+        startedAtNanos = getNanoseconds(CLOCK_MONOTONIC);
+        for (int second = 0; second < durationSeconds; second++) {
+            // Sleep a while. Wake up early if there is an error, for example a DISCONNECT.
+            long ret = myData.waker.wait(AAUDIO_OK, NANOS_PER_SECOND);
+            int64_t millis =
+                    (getNanoseconds(CLOCK_MONOTONIC) - startedAtNanos) / NANOS_PER_MILLISECOND;
+            result = myData.waker.get();
+            printf("wait() returns %ld, aaudio_result = %d, at %6d millis"
+                           ", second = %3d, framesWritten = %8d, underruns = %d\n",
+                   ret, result, (int) millis,
+                   second,
+                   (int) AAudioStream_getFramesWritten(player.getStream()),
+                   (int) AAudioStream_getXRunCount(player.getStream()));
+            if (result != AAUDIO_OK) {
+                disconnected = (result == AAUDIO_ERROR_DISCONNECTED);
+                bailOut = true;
+                break;
             }
+        }
+        printf("AAudio result = %d = %s\n", result, AAudio_convertResultToText(result));
+
+        // Alternate between using stop or pause for each sine/quiet pair.
+        // Repeat this pattern: {sine-stop-quiet-stop-sine-pause-quiet-pause}
+        if ((loopIndex & 2) == 0) {
+            printf("STOP, callback # = %d\n", myData.callbackCount);
+            result = player.stop();
+        } else {
+            printf("PAUSE/FLUSH, callback # = %d\n", myData.callbackCount);
+            result = player.pause();
+            if (result != AAUDIO_OK) {
+                goto error;
+            }
+            result = player.flush();
+        }
+        if (result != AAUDIO_OK) {
+            goto error;
+        }
+
+        if (bailOut) {
             break;
         }
-    }
-    printf("AAudio result = %d = %s\n", result, AAudio_convertResultToText(result));
 
-    printf("call stop() callback # = %d\n", myData.callbackCount);
-    result = player.stop();
-    if (result != AAUDIO_OK) {
-        goto error;
+        {
+            aaudio_stream_state_t state = AAudioStream_getState(player.getStream());
+            aaudio_stream_state_t finalState = AAUDIO_STREAM_STATE_UNINITIALIZED;
+            int64_t timeoutNanos = 2000 * NANOS_PER_MILLISECOND;
+            result = AAudioStream_waitForStateChange(player.getStream(), state,
+                                                     &finalState, timeoutNanos);
+            printf("waitForStateChange returns %s, state = %s\n",
+                   AAudio_convertResultToText(result),
+                   AAudio_convertStreamStateToText(finalState));
+            int64_t written = AAudioStream_getFramesWritten(player.getStream());
+            int64_t read = AAudioStream_getFramesRead(player.getStream());
+            printf("   framesWritten = %lld, framesRead = %lld, diff = %d\n",
+                   (long long) written,
+                   (long long) read,
+                   (int) (written - read));
+        }
+
     }
+
     printf("call close()\n");
     result = player.close();
     if (result != AAUDIO_OK) {
@@ -147,23 +199,54 @@
     return disconnected ? AAUDIO_ERROR_DISCONNECTED : result;
 }
 
+static void usage() {
+    AAudioArgsParser::usage();
+    printf("      -l{count} loopCount start/stop, every other one is silent\n");
+    printf("      -t{msec} play a high pitched tone at the beginning\n");
+}
+
 int main(int argc, const char **argv)
 {
     AAudioArgsParser   argParser;
     aaudio_result_t    result;
+    int32_t            loopCount = 1;
+    int32_t            prefixToneMsec = 0;
 
     // Make printf print immediately so that debug info is not stuck
     // in a buffer if we hang or crash.
     setvbuf(stdout, nullptr, _IONBF, (size_t) 0);
 
-    printf("%s - Play a sine sweep using an AAudio callback V0.1.2\n", argv[0]);
+    printf("%s - Play a sine sweep using an AAudio callback V0.1.3\n", argv[0]);
 
-    if (argParser.parseArgs(argc, argv)) {
-        return EXIT_FAILURE;
+    for (int i = 1; i < argc; i++) {
+        const char *arg = argv[i];
+        if (argParser.parseArg(arg)) {
+            // Handle options that are not handled by the ArgParser
+            if (arg[0] == '-') {
+                char option = arg[1];
+                switch (option) {
+                    case 'l':
+                        loopCount = atoi(&arg[2]);
+                        break;
+                    case 't':
+                        prefixToneMsec = atoi(&arg[2]);
+                        break;
+                    default:
+                        usage();
+                        exit(EXIT_FAILURE);
+                        break;
+                }
+            } else {
+                usage();
+                exit(EXIT_FAILURE);
+                break;
+            }
+        }
     }
 
     // Keep looping until we can complete the test without disconnecting.
-    while((result = testOpenPlayClose(argParser)) == AAUDIO_ERROR_DISCONNECTED);
+    while((result = testOpenPlayClose(argParser, loopCount, prefixToneMsec))
+            == AAUDIO_ERROR_DISCONNECTED);
 
     return (result) ? EXIT_FAILURE : EXIT_SUCCESS;
 }