Moved CreateAudioPlayer related block from opensl_open_playback() to opensl_reset_playback(). This is to fix/properly support ALC_FREQUENCY. The problem is that if you set the frequency to say 22050, the playback is too fast (chipmunk). I believe this is because OpenAL Soft is changing its rate, but the OpenSL backend does not causing the mismatch.

The first problem in the OpenSL backend is that it hard codes the frequency to 44kHz.
The second problem is that the OpenSL backend initializes the player too early. I believe it is initializing at the device opening, and not the context creation where the ALC_FREQUENCY parameter is set/bound to.

So the solution is to move the CreateAudioPlayer stuff to this section which seems to be the reset_callback and respect the Frequency parameter passed through to the callback. I compared to the current mainline OpenAL Soft/OpenSL backend and their implementation seems to place the audio player creation in this same place so this at least makes this implementation more consistent with the official one.

This implementation does suggest to me that it doesn't handle multiple contexts well/correctly, but that is a problem independent of this fix.

jni/OpenAL/Alc/opensles.c

@@ -319,55 +319,6 @@ static ALCboolean opensles_open_playback(ALCdevice *pDevice, const ALCchar *devi
     // create the engine and output mix objects
     SLresult result = alc_opensles_create_native_audio_engine();
 
-    // create buffer queue audio player
-
-    // configure audio source
-    SLDataLocator_AndroidSimpleBufferQueue loc_bufq = {SL_DATALOCATOR_ANDROIDSIMPLEBUFFERQUEUE, 2};
-    SLDataFormat_PCM format_pcm = {SL_DATAFORMAT_PCM, 2, SL_SAMPLINGRATE_44_1,
-        SL_PCMSAMPLEFORMAT_FIXED_16, SL_PCMSAMPLEFORMAT_FIXED_16,
-        SL_SPEAKER_FRONT_LEFT|SL_SPEAKER_FRONT_RIGHT, SL_BYTEORDER_LITTLEENDIAN};
-    SLDataSource audioSrc = {&loc_bufq, &format_pcm};
-
-    // configure audio sink
-    SLDataLocator_OutputMix loc_outmix = {SL_DATALOCATOR_OUTPUTMIX, outputMixObject};
-    SLDataSink audioSnk = {&loc_outmix, NULL};
-
-    // create audio player
-    LOGV("create audio player");
-    const SLInterfaceID ids[1] = {*pSL_IID_ANDROIDSIMPLEBUFFERQUEUE};
-    const SLboolean req[1] = {SL_BOOLEAN_TRUE};
-    result = (*engineEngine)->CreateAudioPlayer(engineEngine, &bqPlayerObject, &audioSrc, &audioSnk,
-        1, ids, req);
-    assert(SL_RESULT_SUCCESS == result);
-
-    // realize the player
-    result = (*bqPlayerObject)->Realize(bqPlayerObject, SL_BOOLEAN_FALSE);
-    assert(SL_RESULT_SUCCESS == result);
-
-    // get the play interface
-    result = (*bqPlayerObject)->GetInterface(bqPlayerObject, *pSL_IID_PLAY, &bqPlayerPlay);
-    assert(SL_RESULT_SUCCESS == result);
-
-    // get the buffer queue interface
-    result = (*bqPlayerObject)->GetInterface(bqPlayerObject, *pSL_IID_BUFFERQUEUE,
-            &bqPlayerBufferQueue);
-    assert(SL_RESULT_SUCCESS == result);
-
-    // register callback on the buffer queue
-    result = (*bqPlayerBufferQueue)->RegisterCallback(bqPlayerBufferQueue, opensles_callback, (void *) pDevice);
-    assert(SL_RESULT_SUCCESS == result);
-
-    // playback_lock = createThreadLock();
-    start_playback(pDevice);
-
-    // set the player's state to playing
-    result = (*bqPlayerPlay)->SetPlayState(bqPlayerPlay, SL_PLAYSTATE_PLAYING);
-    assert(SL_RESULT_SUCCESS == result);
-
-    // enqueue the first buffer to kick off the callbacks
-    result = (*bqPlayerBufferQueue)->Enqueue(bqPlayerBufferQueue, "\0", 1);
-    assert(SL_RESULT_SUCCESS == result);
-
     return ALC_TRUE;
 }
 
@@ -412,8 +363,62 @@ static ALCboolean opensles_reset_playback(ALCdevice *pDevice)
     unsigned channels = ChannelsFromDevFmt(pDevice->FmtChans);
     unsigned samples = pDevice->UpdateSize;
     unsigned size = samples * channels * bits / 8;
+	SLuint32 sampling_rate = pDevice->Frequency * 1000;
+	SLresult result;
     LOGV("bits=%u, channels=%u, samples=%u, size=%u, freq=%u", bits, channels, samples, size, pDevice->Frequency);
-    SetDefaultWFXChannelOrder(pDevice);
+
+    // create buffer queue audio player
+
+    // configure audio source
+    SLDataLocator_AndroidSimpleBufferQueue loc_bufq = {SL_DATALOCATOR_ANDROIDSIMPLEBUFFERQUEUE, 2};
+//    SLDataFormat_PCM format_pcm = {SL_DATAFORMAT_PCM, 2, SL_SAMPLINGRATE_44_1,
+    SLDataFormat_PCM format_pcm = {SL_DATAFORMAT_PCM, 2, sampling_rate,
+        SL_PCMSAMPLEFORMAT_FIXED_16, SL_PCMSAMPLEFORMAT_FIXED_16,
+        SL_SPEAKER_FRONT_LEFT|SL_SPEAKER_FRONT_RIGHT, SL_BYTEORDER_LITTLEENDIAN};
+    SLDataSource audioSrc = {&loc_bufq, &format_pcm};
+
+    // configure audio sink
+    SLDataLocator_OutputMix loc_outmix = {SL_DATALOCATOR_OUTPUTMIX, outputMixObject};
+    SLDataSink audioSnk = {&loc_outmix, NULL};
+
+    // create audio player
+    LOGV("create audio player");
+    const SLInterfaceID ids[1] = {*pSL_IID_ANDROIDSIMPLEBUFFERQUEUE};
+    const SLboolean req[1] = {SL_BOOLEAN_TRUE};
+    result = (*engineEngine)->CreateAudioPlayer(engineEngine, &bqPlayerObject, &audioSrc, &audioSnk,
+        1, ids, req);
+    assert(SL_RESULT_SUCCESS == result);
+
+    // realize the player
+    result = (*bqPlayerObject)->Realize(bqPlayerObject, SL_BOOLEAN_FALSE);
+    assert(SL_RESULT_SUCCESS == result);
+
+    // get the play interface
+    result = (*bqPlayerObject)->GetInterface(bqPlayerObject, *pSL_IID_PLAY, &bqPlayerPlay);
+    assert(SL_RESULT_SUCCESS == result);
+
+    // get the buffer queue interface
+    result = (*bqPlayerObject)->GetInterface(bqPlayerObject, *pSL_IID_BUFFERQUEUE,
+            &bqPlayerBufferQueue);
+    assert(SL_RESULT_SUCCESS == result);
+
+    // register callback on the buffer queue
+    result = (*bqPlayerBufferQueue)->RegisterCallback(bqPlayerBufferQueue, opensles_callback, (void *) pDevice);
+    assert(SL_RESULT_SUCCESS == result);
+
+    // playback_lock = createThreadLock();
+    start_playback(pDevice);
+
+    // set the player's state to playing
+    result = (*bqPlayerPlay)->SetPlayState(bqPlayerPlay, SL_PLAYSTATE_PLAYING);
+    assert(SL_RESULT_SUCCESS == result);
+
+    // enqueue the first buffer to kick off the callbacks
+    result = (*bqPlayerBufferQueue)->Enqueue(bqPlayerBufferQueue, "\0", 1);
+    assert(SL_RESULT_SUCCESS == result);
+
+
+   SetDefaultWFXChannelOrder(pDevice);
 
     return ALC_TRUE;
 }