No audio when recording (also black screen when streaming) with Apple VT Hardware Encoding in M1 MacBook Pro

[did1k]

I'm trying to livestream on YouTube. The YouTube healthcheck says all green and excellent but the preview was all black. The same status also reported in OBS Studio, all green no dropped frames. I suspect something went wrong with the encoder, so I tried to do a recording with the same encoding as my stream setup:

Here is what I do:

• When I press "Record", it is recording video but there is NO AUDIO. Here it is: https://youtu.be/bLczLD0MqPo. I assume this is also the cause of blank black screen when streaming to YouTube.
• And when I changed the encoding into x264, it is working as usual, so I tried streaming: https://youtu.be/RhOLE_MjNkA However, it looks choppy and encoding often overloaded.
• This is my log: https://obsproject.com/tools/analyzer?log_url=https://obsproject.com/logs/5Cl1zaJmqBlXbsFO

Any idea of what is causing the VT H264 Hardware Encoder to lose the audio?

 

[Aureliano]

Hi there.
I'm using OBS to record my old VHS tapes on my MBA M1.
I was having the same issue as you. I was using Hardware Apple VT to record but the final file was missing the audio track. What worked for me was to uncheck the Limit bitrate box and now it records both video and audio.
I'm not streaming at any platform, and I know that the limit bitrate is a must when you stream, but this solution works for me.
I don't know if it is a M1 related bug or an Apple VT bug in both Intel and Apple chips.
Love from Bogotá.

 

[PC_Junkie_17]

Hi everyone,
So this is definitely an issue with the M1 Macs as the Intel Macs work just fine. I have an M1 Mac and an Intel Mac and I have no issue recording or streaming audio and video at the same time from the Intel Mac. Since the M1 Macs are running a variation of the ARM Architecture and not an x86-64 based architecture some of the calls in the current Intel version are not working right now. Until the OBS Project puts out an Apple Silicon version of the OBS software this issue will still persist and there's no way around it that I know of at this time.