diff --git a/services/audioflinger/FastMixer.cpp b/services/audioflinger/FastMixer.cpp
index 80e37ca..2832e96 100644
--- a/services/audioflinger/FastMixer.cpp
+++ b/services/audioflinger/FastMixer.cpp
@@ -120,12 +120,13 @@
         FastMixerState::Command command = next->mCommand;
         if (next != current) {
 
-            logWriter->log("next != current");
-
             // As soon as possible of learning of a new dump area, start using it
             dumpState = next->mDumpState != NULL ? next->mDumpState : &dummyDumpState;
             teeSink = next->mTeeSink;
             logWriter = next->mNBLogWriter != NULL ? next->mNBLogWriter : &dummyLogWriter;
+            if (mixer != NULL) {
+                mixer->setLog(logWriter);
+            }
 
             // We want to always have a valid reference to the previous (non-idle) state.
             // However, the state queue only guarantees access to current and previous states.
@@ -167,7 +168,6 @@
                 ALOG_ASSERT(coldFutexAddr != NULL);
                 int32_t old = android_atomic_dec(coldFutexAddr);
                 if (old <= 0) {
-                    logWriter->log("wait");
                     __futex_syscall4(coldFutexAddr, FUTEX_WAIT_PRIVATE, old - 1, NULL);
                 }
                 // This may be overly conservative; there could be times that the normal mixer
@@ -186,7 +186,6 @@
             }
             continue;
         case FastMixerState::EXIT:
-            logWriter->log("exit");
             delete mixer;
             delete[] mixBuffer;
             return false;
@@ -264,15 +263,11 @@
             unsigned currentTrackMask = current->mTrackMask;
             dumpState->mTrackMask = currentTrackMask;
             if (current->mFastTracksGen != fastTracksGen) {
-                logWriter->logf("gen %d", current->mFastTracksGen);
                 ALOG_ASSERT(mixBuffer != NULL);
                 int name;
 
                 // process removed tracks first to avoid running out of track names
                 unsigned removedTracks = previousTrackMask & ~currentTrackMask;
-                if (removedTracks) {
-                    logWriter->logf("removed %#x", removedTracks);
-                }
                 while (removedTracks != 0) {
                     i = __builtin_ctz(removedTracks);
                     removedTracks &= ~(1 << i);
@@ -292,9 +287,6 @@
 
                 // now process added tracks
                 unsigned addedTracks = currentTrackMask & ~previousTrackMask;
-                if (addedTracks) {
-                    logWriter->logf("added %#x", addedTracks);
-                }
                 while (addedTracks != 0) {
                     i = __builtin_ctz(addedTracks);
                     addedTracks &= ~(1 << i);
@@ -322,17 +314,15 @@
                     generations[i] = fastTrack->mGeneration;
                 }
 
-                // finally process modified tracks; these use the same slot
+                // finally process (potentially) modified tracks; these use the same slot
                 // but may have a different buffer provider or volume provider
                 unsigned modifiedTracks = currentTrackMask & previousTrackMask;
-                if (modifiedTracks) {
-                    logWriter->logf("modified %#x", modifiedTracks);
-                }
                 while (modifiedTracks != 0) {
                     i = __builtin_ctz(modifiedTracks);
                     modifiedTracks &= ~(1 << i);
                     const FastTrack* fastTrack = &current->mFastTracks[i];
                     if (fastTrack->mGeneration != generations[i]) {
+                        // this track was actually modified
                         AudioBufferProvider *bufferProvider = fastTrack->mBufferProvider;
                         ALOG_ASSERT(bufferProvider != NULL);
                         if (mixer != NULL) {
@@ -453,7 +443,7 @@
             ATRACE_END();
             dumpState->mWriteSequence++;
             if (framesWritten >= 0) {
-                ALOG_ASSERT(framesWritten <= frameCount);
+                ALOG_ASSERT((size_t) framesWritten <= frameCount);
                 dumpState->mFramesWritten += framesWritten;
                 //if ((size_t) framesWritten == frameCount) {
                 //    didFullWrite = true;
@@ -471,7 +461,7 @@
         struct timespec newTs;
         int rc = clock_gettime(CLOCK_MONOTONIC, &newTs);
         if (rc == 0) {
-            logWriter->logTimestamp(newTs);
+            //logWriter->logTimestamp(newTs);
             if (oldTsValid) {
                 time_t sec = newTs.tv_sec - oldTs.tv_sec;
                 long nsec = newTs.tv_nsec - oldTs.tv_nsec;