diff --git a/audio/core/all-versions/default/ParametersUtil.cpp b/audio/core/all-versions/default/ParametersUtil.cpp
index c0e2903..eb2d2c2 100644
--- a/audio/core/all-versions/default/ParametersUtil.cpp
+++ b/audio/core/all-versions/default/ParametersUtil.cpp
@@ -97,15 +97,15 @@
             retval = getHalStatusToResult(status);
             break;
         }
-        result[i].key = halKey.string();
-        result[i].value = halValue.string();
+        result[i].key = halKey.c_str();
+        result[i].value = halValue.c_str();
     }
     cb(retval, result);
 }
 
 std::unique_ptr<AudioParameter> ParametersUtil::getParams(const AudioParameter& keys) {
     String8 paramsAndValues;
-    char* halValues = halGetParameters(keys.keysToString().string());
+    char* halValues = halGetParameters(keys.keysToString().c_str());
     if (halValues != NULL) {
         paramsAndValues.setTo(halValues);
         free(halValues);
@@ -163,7 +163,7 @@
 }
 
 Result ParametersUtil::setParams(const AudioParameter& param) {
-    int halStatus = halSetParameters(param.toString().string());
+    int halStatus = halSetParameters(param.toString().c_str());
     return util::analyzeStatus(halStatus);
 }
 
diff --git a/audio/core/all-versions/default/Stream.cpp b/audio/core/all-versions/default/Stream.cpp
index 8e85a8b..c11b675 100644
--- a/audio/core/all-versions/default/Stream.cpp
+++ b/audio/core/all-versions/default/Stream.cpp
@@ -114,7 +114,7 @@
     SampleRateSet halSampleRates;
     if (result == Result::OK) {
         halSampleRates =
-            samplingRatesFromString(halListValue.string(), AudioParameter::valueListSeparator);
+                samplingRatesFromString(halListValue.c_str(), AudioParameter::valueListSeparator);
         sampleRates = hidl_vec<uint32_t>(halSampleRates.begin(), halSampleRates.end());
         // Legacy get_parameter does not return a status_t, thus can not advertise of failure.
         // Note that this method must succeed (non empty list) if the format is supported.
@@ -140,7 +140,7 @@
     ChannelMaskSet halChannelMasks;
     if (result == Result::OK) {
         halChannelMasks =
-            channelMasksFromString(halListValue.string(), AudioParameter::valueListSeparator);
+                channelMasksFromString(halListValue.c_str(), AudioParameter::valueListSeparator);
         channelMasks.resize(halChannelMasks.size());
         size_t i = 0;
         for (auto channelMask : halChannelMasks) {
@@ -182,7 +182,7 @@
     hidl_vec<AudioFormat> formats;
     FormatVector halFormats;
     if (result == Result::OK) {
-        halFormats = formatsFromString(halListValue.string(), AudioParameter::valueListSeparator);
+        halFormats = formatsFromString(halListValue.c_str(), AudioParameter::valueListSeparator);
         formats.resize(halFormats.size());
         for (size_t i = 0; i < halFormats.size(); ++i) {
             formats[i] = AudioFormat(halFormats[i]);
@@ -226,7 +226,7 @@
     // Ensure that the separator is one character, despite that it's defined as a C string.
     static_assert(sizeof(AUDIO_PARAMETER_VALUE_LIST_SEPARATOR) == 2);
     std::vector<std::string> halFormats =
-            splitString(halListValue.string(), AUDIO_PARAMETER_VALUE_LIST_SEPARATOR[0]);
+            splitString(halListValue.c_str(), AUDIO_PARAMETER_VALUE_LIST_SEPARATOR[0]);
     hidl_vec<AudioFormat> formats;
     (void)HidlUtils::audioFormatsFromHal(halFormats, &formats);
     std::vector<AudioProfile> tempProfiles;
@@ -241,7 +241,7 @@
         result = getParam(AudioParameter::keyStreamSupportedSamplingRates, &halListValue, context);
         if (result != Result::OK) break;
         std::vector<std::string> halSampleRates =
-                splitString(halListValue.string(), AUDIO_PARAMETER_VALUE_LIST_SEPARATOR[0]);
+                splitString(halListValue.c_str(), AUDIO_PARAMETER_VALUE_LIST_SEPARATOR[0]);
         hidl_vec<uint32_t> sampleRates;
         sampleRates.resize(halSampleRates.size());
         for (size_t i = 0; i < sampleRates.size(); ++i) {
@@ -251,7 +251,7 @@
         result = getParam(AudioParameter::keyStreamSupportedChannels, &halListValue, context);
         if (result != Result::OK) break;
         std::vector<std::string> halChannelMasks =
-                splitString(halListValue.string(), AUDIO_PARAMETER_VALUE_LIST_SEPARATOR[0]);
+                splitString(halListValue.c_str(), AUDIO_PARAMETER_VALUE_LIST_SEPARATOR[0]);
         hidl_vec<AudioChannelMask> channelMasks;
         (void)HidlUtils::audioChannelMasksFromHal(halChannelMasks, &channelMasks);
         // Create a profile.