Unexpected Problem When ASIO Buffer Size Increased

[Bill Phillips]

I was getting lots of sizzling when I moved the cursor around over the CbB window and opened and closed plugins with an ASIO buffer size of 64 samples. My usual solution is to increase the ASIO buffer size to 1024 samples, but that caused the audio engine to dropout instantly. So I tried 256 samples which cured the dropout but playback was unintelligible. I looked up the dropout code (1) which suggested increasing buffer size which hadn't worked this time. I looked at other settings. The only change I made was to change Synchronization from Full Chase Lock to Trigger & Freewheel since my MOTU 828 mkII has a word clock. This didn't help.

I made a gif showing me working through the ASIO buffer size changes and how CbB reacted:

1. I started with a buffer size of 64 samples and playback is ok except for a little sizzling. Note the performance meter shows a reasonable load though the max engine load is 140% and there are some late buffers. But playback is usable for mixing when the cursor isn't moving.
2. I next switched to 256 samples and the CPU thread load bars actually bounced up but the max engine load did drop to 105% and the number of late buffers didn't significantly change. But playback was unintelligible.
3. I next switched to 1024 samples and the audio engine dropped out with (1) dropout code indicating that a the buffer size should be increased but that's not possible and increasing the buffer size seems to increase not reduce the problem severity.
4. I switched back to 64 samples and the audio engine restarted and playback was usable.

Edited May 13, 2021 by Bill Phillips

[scook]

Try setting StopEngineOnASIOPanelOpen to  True in Preferences > Audio > Configuration File

After changing the value click "Reload Config Setting" at the top of preferences.

[Bill Phillips]

12 hours ago, scook said:

Try setting StopEngineOnASIOPanelOpen to  True in Preferences > Audio > Configuration File

After changing the value click "Reload Config Setting" at the top of preferences.

Thanks. It's already True. This is counter intuitive. I'm having trouble imagining how increasing the number of samples in the I/O buffer could degrade performance. I don't recall this ever happening before. However, I'm able to keep working on the project with 64 samples with crackling.