Almost 100% related to drivers: https://www.dell.com/community/Alienware/x17-R1-audio-stops-working-when-switching-applications-randomly/m-p/8321698#M56735 I currently have 6.0.9394.1 installed with no way to roll back using the instructions on page 2 of the linked post, some incompatibility with the latest W11 update 22H2 is preventing it.
My problem is that with an external speaker plugged in, a period of 1 min of inactivity on the audio output will cause the 3.5mm jack output line to go completely dead. No sound comes out of it after that. Only way to "revive" it is to enable/disable mono audio in Settings—>Audio, or to switch to a different output device, then back to it. The issue then recurs after a period of use and then inactivity.
Currently have no way to roll back my drivers to an older version with any of the provided Realtek installers. They only remove the old version, then upon restart, the latest audio driver is downloaded and installed automatically (9394).