Is there a simple way to turn system speakers off at a particular time (e.g. quiet time overnight) and back on again afterwards - whilst leaving any Bluetooth sound connections unaffected - so that I can connect headphones and listen to stuff at any time?
I'm using Ubuntu 22.04 on a Thinkpad, if this is relevant and am still pretty much a noob. I imagine that cron jobs may come into play here.
TIA.