diff --git a/include/media/ToneGenerator.h b/include/media/ToneGenerator.h
index e8df08e..c884c2c 100644
--- a/include/media/ToneGenerator.h
+++ b/include/media/ToneGenerator.h
@@ -248,6 +248,7 @@
     // only if tone duration is less than about 27 Hours(@44100Hz sampling rate). If this time is exceeded,
     // no crash will occur but tone sequence will show a glitch.
     unsigned int mMaxSmp;  // Maximum number of audio samples played (maximun tone duration)
+    int mDurationMs;  // Maximum tone duration in ms
 
     unsigned short mCurSegment;  // Current segment index in ToneDescriptor segments[]
     unsigned short mCurCount;  // Current sequence repeat count
diff --git a/media/libmedia/ToneGenerator.cpp b/media/libmedia/ToneGenerator.cpp
index d36bec9..3729eb3 100644
--- a/media/libmedia/ToneGenerator.cpp
+++ b/media/libmedia/ToneGenerator.cpp
@@ -879,6 +879,7 @@
 ////////////////////////////////////////////////////////////////////////////////
 bool ToneGenerator::startTone(int toneType, int durationMs) {
     bool lResult = false;
+    status_t lStatus;
 
     if ((toneType < 0) || (toneType >= NUM_TONES))
         return lResult;
@@ -898,15 +899,16 @@
     toneType = getToneForRegion(toneType);
     mpNewToneDesc = &sToneDescriptors[toneType];
 
-    if (durationMs == -1) {
-        mMaxSmp = TONEGEN_INF;
-    } else {
-        if (durationMs > (int)(TONEGEN_INF / mSamplingRate)) {
-            mMaxSmp = (durationMs / 1000) * mSamplingRate;
-        } else {
-            mMaxSmp = (durationMs * mSamplingRate) / 1000;
+    mDurationMs = durationMs;
+
+    if (mState == TONE_STOPPED) {
+        LOGV("Start waiting for previous tone to stop");
+        lStatus = mWaitCbkCond.waitRelative(mLock, seconds(1));
+        if (lStatus != NO_ERROR) {
+            LOGE("--- start wait for stop timed out, status %d", lStatus);
+            mState = TONE_IDLE;
+            return lResult;
         }
-        LOGV("startTone, duration limited to %d ms", durationMs);
     }
 
     if (mState == TONE_INIT) {
@@ -919,7 +921,7 @@
             mLock.lock();
             if (mState == TONE_STARTING) {
                 LOGV("Wait for start callback");
-                status_t lStatus = mWaitCbkCond.waitRelative(mLock, seconds(1));
+                lStatus = mWaitCbkCond.waitRelative(mLock, seconds(1));
                 if (lStatus != NO_ERROR) {
                     LOGE("--- Immediate start timed out, status %d", lStatus);
                     mState = TONE_IDLE;
@@ -931,9 +933,8 @@
         }
     } else {
         LOGV("Delayed start\n");
-
         mState = TONE_RESTARTING;
-        status_t lStatus = mWaitCbkCond.waitRelative(mLock, seconds(1));
+        lStatus = mWaitCbkCond.waitRelative(mLock, seconds(1));
         if (lStatus == NO_ERROR) {
             if (mState != TONE_IDLE) {
                 lResult = true;
@@ -1316,6 +1317,17 @@
 
     mpToneDesc = mpNewToneDesc;
 
+    if (mDurationMs == -1) {
+        mMaxSmp = TONEGEN_INF;
+    } else {
+        if (mDurationMs > (int)(TONEGEN_INF / mSamplingRate)) {
+            mMaxSmp = (mDurationMs / 1000) * mSamplingRate;
+        } else {
+            mMaxSmp = (mDurationMs * mSamplingRate) / 1000;
+        }
+        LOGV("prepareWave, duration limited to %d ms", mDurationMs);
+    }
+
     while (mpToneDesc->segments[segmentIdx].duration) {
         // Get total number of sine waves: needed to adapt sine wave gain.
         unsigned int lNumWaves = numWaves(segmentIdx);