Just giggled as my last meme mentioned trouble with displays and appropriately, a large chunk of the replies were “well MY displays work just fine!” (And charmingly, many were thoughts of things to check, other distros etc. It’s a very kind community, though that may also be the fediverse.)
Audio! I went from stereo to 7.1 and got this intense loud buzz that wouldn’t go away! (Fedora KDE). Drove me nuts. Spent hours trying every dang thing. Finally connected it to a Windows machine. Same buzz. My woofer had just ate itself. Nothing to do with Linux at all.