Page 1 of 1

Dropouts when recording through VB-Cable

Posted: Thu Mar 18, 2021 5:40 pm
by jacobacci
After solving my initial issue of misconfiguring Audacity, I am happily recording from Roon through VB Cable to Audacity.
When I looked at the recorded files in Audacity, I noticed that there are dropouts of around 0.1 second length at irregular intervals during the recording. They are not very frequent, but frequent enough to be annoying. During the dropout the signal seems to be a perfect zero. The db scale of the Audacity display shows no amplitude at all.
This is what such a dropout looks like:

Audacity2.jpg
Audacity2.jpg (243.16 KiB) Viewed 26296 times

I get these dropouts under Windows 10 and also under MacOS BigSur 11.2.3 During recording no other tasks are preformed on the computer.
I would appreciate any suggestions what might be the issue here.

Re: Dropouts when recording through VB-Cable

Posted: Fri Mar 19, 2021 8:16 am
by Vincent Burel
not expected to happen (0.1s is around one 4096 sample buffer).
could you post a screenshot of your VBCABLE Contol panel?
maybe the internal latency is not big enough.

Re: Dropouts when recording through VB-Cable

Posted: Sat Mar 20, 2021 10:16 am
by jacobacci
Here's a screenshot of the Control Panel. As my use case is not latency sensitive at all, what would be the maximum to use for a safety cushion?


1.jpg
1.jpg (147.29 KiB) Viewed 26283 times

Re: Dropouts when recording through VB-Cable

Posted: Sat Mar 20, 2021 1:00 pm
by jacobacci
I have now increased latency to 12288smp and I have indeed seen a reduction in dropouts. With a latency of 6144smp, I had 5 dropouts in the ca. 1 hour recording. With 12288smp I only had one. It would be great to find a way to get none.
I am wondering if it would help to set the output of Roon to use exclusive mode?
Here's the screenshot:

2.jpg
2.jpg (247.45 KiB) Viewed 26279 times

Re: Dropouts when recording through VB-Cable

Posted: Sat Mar 20, 2021 5:01 pm
by jacobacci
I think I have figured out what the issue was / is.
At first, the latency was too low, that's why I got 5 dropouts. After increasing the latency, the numbers of dropouts reduced to one and I was able to trace that one to a dropout in the source file.
I have now redownloaded the album from Qobuz and I am not getting any more dropouts.
Happy camper, thank you

Re: Dropouts when recording through VB-Cable

Posted: Mon Mar 22, 2021 8:40 am
by Vincent Burel
if both application (player and recorder) use 4096 buffer, the internal cable latency must be 3x 4096 samples.
=12288 sample = min siez to have something working...

but for security you may set it to 4x or 5x 4096 samples