If you’ve looked up how to install Xbox Game Pass on Steam Deck or anything else that involves desktop mode tomfoolery, you’ll know that plugging in a mouse and keyboard is almost mandatory.
As I got sucked into the Steam Deck, I started to dig into more of what it could be coaxed into doing. Some fiddling about and pouring over guides and I now have access to my GOG library and Xbox ...
If you don't see it at first, reboot your Steam Deck. I've had to do this a few times with Decky Loader plugins. You can manage your different system sound packs from within the Audio Loader ...