Partial hearing loss is a not uncommon side effect of COVID infection, and tinnitus a not uncommon side effect of hearing loss. Anything that causes inflammation in the wrong areas can do it, but COVID is the main one right now and why audiologists are busy. There is a steroid treatment that apparently can help if prescribed almost immediately (48 hours?), but it didn't help in a family members case.
Mine started after covid also, see further up tho it actually recently stopped and i couldn't figure out what had changed apart from taking a complex b supplement for a couple months.. Cant hurt maybe?
it's not too bad, only one ear and it comes and goes pretty quickly.
For me the COVID correlation is 100%, but I haven't found too much literature about it and wonder if anyone experienced it as well