A little while after getting Covid-19, I noticed that my tinnitus was more intrusive. It didn't seem more intense, but while I used to pretty much tune it out all the time and only really noticed it when the subject got raised, or on the occasions (maybe every couple of months) when for some reason it got louder for a while, now it's more noticeable. I wondered if it might be Covid related as Mrs Zero has had her sense of taste affected, so there are presumably potentially some neurological effects, and I finally got round to using a popular search engine to check it out. And this is what I found: https://www.thebsa.org.uk/covid-19-is-making-tinnitus-worse-new-study/
So if you have tinnitus, beware of Covid. Beware of it anyway, but it's just another reason to keep clear and get vaccinated as soon as you can.