AudioMixerPlayable is not working well and binding not working

Hi. I've tested playable these days. I found the animation mixer playable works quite well for Unity 2018.3.1f.
However, the AudioMixerPlayable is still not working well. I connect 3 audio playable to the (channel 0,1,2 of) an audioMixerPlayable and the 3rd channel is always not working regardless of the weight value. Only the first two channels works. I've checked the connection in Runtime with PlayableGraph Visualizer. The connection seems to be right, I could see the 3rd channel is highlighted while other 2 is grey, thus still no sound comes out of the third channel. Is it a bug?


Another issue is the binding the audio output to an audio source is also not working.
I bind the audio output to an audio source, however, even if the audio source is disabled, the sound still plays.

audOutput = AudioPlayableOutput.Create(playG, "AudioOut", GetComponent<AudioSource>());

Does anyone have any ideas about it?

 

i also find this issue happens in latest unity version, did you manage to resolve this???