Apple

AUGRAPH_CHECK( AUGraphSetNodeInputCallback ( _graph, outputNode, 0, &callback ) );

AUGRAPH_CHECK( AUGraphConnectNodeInput( _graph, speechNode, 0, outputNode, 0 ) );

I am presented with kAUGraphErr_InvalidConnection from AUGraphConnectNodeInput - to me this makes sense because I've already informed the graph I will provide input to outputNode via my callback.

Attempting the following:

AU_CHECK( AudioUnitSetProperty( _outputUnit, kAudioUnitProperty_SetRenderCallback, kAudioUnitScope_Input, 0, &callback, sizeof(callback)) );

AUGRAPH_CHECK( AUGraphConnectNodeInput( _graph, speechNode, 0, outputNode, 0 ) );

will not produce an error, but my callback is not fired. What seems to be missing to me is a method like AUGraphConnectRenderCallback... is this incorrect?

References:
	>Re: getting generator audio unit output in render callback (From: Rich E <email@hidden>)