Think this may be triggered by entering comment section and returning to video.
A byte will skip back to the beginning after a few seconds and keep doing this, it seems to affect every byte when scrolling.
Possibly related, sometimes when scrolling and then stopping to watch a byte it plays a couple seconds then scrolls back up by itself. Which may also be related to bug where by jiggling up and down a bit on the most recent post on my own profile (doesn’t happen on other profiles) I can make the screen shake up and down endlessly.
Can’t reliably recreate the skip and auto scroll but the wiggle can be.