Hi.
I'd the same problem since the last update (35.0.0.141.341.339081697)
It didn't sound in the menu, in stand-alone games, or even in PC games via Air Link nor Oculus Link cable... no sounds at all.
The way I've just fixed the issue was:
1- Turn on Oculus Quest 2
2- Connect headphones via mini-jack (it made the sound starts working via headphones...)
3- Turn Off Quest 2 normally
4- Start again Oculus Quest 2 (don't just restart.. turn off and then on...)
5- When Quest menu started, just unplug headphones mini-jack, and then, magically sound is restored through Oculus Quest 2 speakers.
Maybe doing other things like plug/unplug jack headphones without restarting or other steps, may fix the problem, but in my case, those were the steps I followed, and couldn't try any other steps once the problem was fixed.
I expect to be helpful to others.
Cheers