can confirm that it’s a constant sine wave, at least for me.
i blew myself up by accident a month ago, and while my left ear has fully recovered my right one wasn’t so lucky. lost all hearing above like 10kHz (which isnt really noticeable, especially with my left ear still being good on frequencies), and i also now have some very minor tinnitus there. ironically if i had to guesstimate the frequency of my tinnitus it would be around 12 kHz, which is past my hearing range, though it can change briefly because of external stimuli.
Based on the other responses to this, I’d say it really varies from person to person.
In my case, Kdenlive does in fact tend to crash often the longer I use it in a single session. It tends to get unstable on my system after around 2-3 hours of continuous work.
I remember losing an hour’s worth of progress once, and from that point I’ve been saving my stuff compulsively. At least it taught me good habits!