I use FMOD_OUTPUTTYPE_WAVWRITER_NRT, but not work

FMOD Engine
1 
result = system->setOutput(FMOD_OUTPUTTYPE_WAVWRITER_NRT);
    ERRCHECK(result);
    
   char cDest[200] = {0};
    NSString *fileName=[NSString stringWithFormat:@"%@/addeffects_sound.wav", [NSSearchPathForDirectoriesInDomains(NSDocumentDirectory, NSUserDomainMask, YES) objectAtIndex:0]];
    [fileName getCString:cDest maxLength:200 encoding:NSASCIIStringEncoding];
    
    printf(fileName.cString);
    result = system->init(32, FMOD_INIT_NORMAL, cDest);
    
   // result = system->init(32, FMOD_INIT_NORMAL, extradriverdata);
    //ERRCHECK(result);

    result = system->getMasterChannelGroup(&mastergroup);
    ERRCHECK(result);

    result = system->createSound(Common_MediaPath("drumloop.wav"), FMOD_DEFAULT, 0, &sound);
    ERRCHECK(result);

    result = system->playSound(sound, 0, false, &channel);
    ERRCHECK(result);

////I add up code to effects.cpp, and it will create addeffects_sound.wav. and i add dap to it. but can not play . why? please help me

2

You need to call System::update to operate the non-realtime version of wav writer. Each call to System::update will generate 1 DSP block of samples which is usually 1024 samples.