I'm having an issue similar to one described here: https://forum.parallels.com/threads/keep-losing-sound-windows-10.342035/ In my case, I'm running MacOS 10.15.4 on a MBP-16" Parallels 15.1.4 VM is Windows 10 My issue is: I will randomly lose sound when using Parallels. Until I lose it, it is working fine... from both the built-in speakers and if i plug in headphones. But once it stops working... I can't get the sound to come back on until the Parallells/VM is restarted... I don't need to re-start the Mac/MacOS itself, nor restart Paraellels.. I only need to restart the Win10-OS. Again,,, it is random... sometimes it seems to happen "right away" once the Win10 machine is started, sometimes it happens after an hour or so of using it. But it always seems to happen after a while. Since the sound works fine until it happens, i'm thinking this is some kind of bug rather than a configuration issue, etc?