Ask Your Question

Isochronous audio data missing

asked 2023-12-12 22:09:52 +0000

xio gravatar image

I'm recording audio from a microphone and I noticed that sometimes ISO packets don't have any data in them during active recording. Recordings work perfectly fine on a Windows PC but have issues on Mac, such as audio drops, repeats etc.

Usually I'd see something like this while I'm recording in the USB isochronous packet:

ISO Data offset: xxxx

ISO Data length: 0x00000020 (relevant) //Max packet size is 32 Bytes

ISO USBD status: xxxx

ISO Data: Hex Data

But sometimes in between Hex Data packets, I'd see empty packets with no data at all, not even 0s.

ISO Data offset: xxxx

ISO Data length: 0x00000000 (relevant)

ISO USBD status: xxxx

ISO Data field is missing

My guess is that these missing data packets are responsible for the behavior on Mac. Are these packets considered Zero Length Packets telling host transmission is over? Even though more data is still coming in?

edit retag flag offensive close merge delete

1 Answer

Sort by ยป oldest newest most voted

answered 2023-12-15 19:55:12 +0000

NOORA gravatar image

Update System and Drivers:

Ensure your Mac's operating system is up-to-date, as updates often include fixes for hardware compatibility issues. Check if there are any specific drivers for your audio device that need to be updated.

edit flag offensive delete link more

Your Answer

Please start posting anonymously - your entry will be published after you log in or create a new account.

Add Answer

Question Tools

1 follower


Asked: 2023-12-12 22:09:52 +0000

Seen: 52 times

Last updated: Dec 15 '23