Obscure audio issue

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As mentioned elsewhere I'm running an external DAC for my audio needs and on my main system the quality & performance is excellent. However, I have secondary PC that I do all my work stuff on and the DAC spazzes out from time to time

Current set up:

Single monitor, mouse, keyboard, DAC into a KVM. KVM Port 1 = custom AMD gaming system. KVM Port 2 = Dell Intel-based desktop. DisplayPort and a single USB cable are the only connections from the PCs.

Issue:

Listening to a continuous audio stream, e.g. digital radio, podcast, Zoom meeting, the audio with suddenly turn into a sort of digital static. Pausing the source of the audio stream stops the static, unpausing it immediately the static starts up again. It's some sort of digital garbled version of the original stream as the noise is vaguely proportional to the source. Apologies for the poor description. The noise starts up seemingly randomly probably 2 or 3 times a day.

Quick fix:

Obviously the ol' off & on trick for the DAC sorts things but also pausing the source stream for long enough to Windows to disconnect the stream also works. Essentially a very minimal soft-reset does the trick.

Things I have tried:

I've tried a couple of KVMs but they both exhibit the same problem as does a separate USB switcher. I've tried a USB ground-loop/noise isolator box on the Dell ports to no avail. Manually plugging the DAC into the AMD or Dell system, i.e. not through either a KVM or USB switcher and the problem goes away

What I believe is happening is some sort of event disturbing the data stream flowing to the DAC and therefore the following data is out of sync and rendered nonsensical. Very occasionally I might also see a visual glitch on my monitor (from the Dell) and I'm wondering if the DAC is receiving a similar glitch. And before you ask: I haven't seen a visual glitch at the same time as the audio going wonky. The visual glitches rarely happen (maybe >1 week apart) and the picture recovers instantly in the next frame.

The only clue I might have is in my previous setup where the onboard soundcards of both systems fed to the KVM and that arrangement exhibited an unbearable ground-loop problem. And while standard audio ground-loop isolators killed the background noise they also killed the quality hence the move to external DAC.

I know if I change to a mechanical USB switch for the DAC rather than digital I'll have no problems (effectively the same as unplugging from one system and plugging into the other) but dammit, we're in premium First World Problems territory here: I'd have two switch boxes and I'd have to turn the DAC back on. FML, etc.
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