I'm troubleshooting this issue with a new client. She has an HP ProBook 450 G6 Win10 Pro 1909. Seems to only happen in Zoom Meetings. Randomly mic and speakers stop then F5/F8 turn on. Turn them off and everything is fine again. She setup the laptop 12/30/19 and has been trying to troubleshoot it for a couple of months. I saw a thread on Reddit about this also, but the original poster ended up circumventing the issue by having affected people use USB headsets.