Apple

Hi all,

I wonder if there's any limit to the number of input buses a kAudioUnitType_Mixer can use. I empirically found that buses higher than ~8 are discarded. That means that I can mix up to 7 inputs but the 8th and higher are silent in the output mix.

I tried with kAudioUnitSubType_MultiChannelMixer, kAudioUnitSubType_StereoMixer and kAudioUnitSubType_3DMixer sub-types. All input buses are set to mono 44100hz and the mixer output is stereo.

I got the same behavior regardless whether I connected other nodes to the mixer input buses or using render input callbacks.

We are calling setting setting the kAudioUnitProperty_ElementCount property with the right value (e.g. 11 buses).

Does anyone have an idea of what's going on? I was thinking about using N number of mixers and connecting them to a master mix but that sounds like a hack to me and I'd love to understand what's going on first.

Thanks

Marcelo

References:
	>kAudioUnitType_Mixer limit? (From: Marcelo Birnbach <email@hidden>)