openAL streaming & interruptions - iphone

Question

I made an iphone application which uses OpenAL to play many sounds.
These sounds are in mp3, quite heavy (more than 1mn)and I stream them (2 buffers per sound) in order to use less memory.
To manage interruptions, I use this code :
In OpenALSupport.c file :
//used to disable openAL during a call
void openALInterruptionListener ( void *inClientData, UInt32 inInterruptionState)
{
if (inInterruptionState == kAudioSessionBeginInterruption)
{
alcMakeContextCurrent (NULL);
}
}
//used to restore openAL after a call
void restoreOpenAL(void* a_context)
{
alcMakeContextCurrent(a_context);
}
In my SoundManager.m file :
- (void) restoreOpenAL
{
restoreOpenAL(mContext);
}
//OPENAL initialization
- (bool) initOpenAL
{
// Initialization
mDevice = alcOpenDevice(NULL);
if (mDevice) {
...
// use the device to make a context
mContext=alcCreateContext(mDevice,NULL);
// set my context to the currently active one
alcMakeContextCurrent(mContext);
AudioSessionInitialize (NULL, NULL, openALInterruptionListener, mContext);
NSError *activationError = nil;
[[AVAudioSession sharedInstance] setActive: YES error: &activationError];
NSError *setCategoryError = nil;
[[AVAudioSession sharedInstance] setCategory: AVAudioSessionCategoryAmbient error: &setCategoryError];
...
}
And finally in my AppDelegate :
- (void)applicationDidBecomeActive:(UIApplication *)application
{
[[CSoundManager getInstance] restoreOpenAL];
...
}
With this method the sounds are back after a call , but flows seem to be played randomly.
Is there a specific way to manage interruption with streaming sounds ? I don't find any article about that.
Thanks for your help.

Answer 1

Ok, I answer to my own question.
I solved the problem by managing error on my streaming method :
- (void) updateStream
{
ALint processed;
alGetSourcei(sourceID, AL_BUFFERS_PROCESSED, &processed);
while(processed--)
{
oldPosition = position;
NSUInteger buffer;
alSourceUnqueueBuffers(sourceID, 1, &buffer);
////////////////////
//code freshly added
ALint err = alGetError();
if (err != 0)
{
NSLog(#"Error Calling alSourceUnQueueBuffers: %d",err);
processed++;
//restore old position for the next buffer
position = oldPosition;
usleep(10000);
continue;
}
////////////////////
[self stream:buffer];
alSourceQueueBuffers(sourceID, 1, &buffer);
////////////////////
//code freshly added
err = alGetError();
if (err != 0)
{
NSLog(#"Error Calling alSourceQueueBuffers: %d",err);
processed++;
usleep(10000);
//restore old position for the next buffer
position = oldPosition;
}
///////////////////
}
}