While VLC runs, I find that my keyboard becomes very erratic. It repeats letters, misses letters, changes up the order, puts several seconds worth of lag between input and display, varying the combinations of these effects seemingly at random. This happens when audio or video is running, but recently the effect has persisted even several minutes after VLC is closed and the process killed just to make sure.
The same effect happens with other video/audio players (MPV video player, Rhythmbox), but it does not happen when playing video through YouTube. The effect does not correlate with any other lag, the system works fine, any interaction I can accomplish with just the mouse works fine and smoothly. It also only affects a USB-connected wireless keyboard (I have a notebook and its built-in keyboard works fine). I figured it might be the wireless part that's having trouble, so I tried disabling Bluetooth on the computer, to no effect. The mouse is also USB-connected (with a wire), but it's unaffected. I run Ubuntu 20.04.3 LTS.
How do I even approach such an issue?
