I had classical and big band sounding music in my head following my 3rd Covid Vaccination. It last about a month and made it hard to sleep. It did resolve itself.

For the past 4 years, I have been hearing songs that I recognize by a group that I would describe as a talented quartet. Volume is at a very acceptable level. I keep a list of the songs on my "Juke Box" and they total about 130. The music never interrupts conversations or activities. I had a brain scan and related tests and counsel and everything came out negative. A song will sometimes repeat but I can quickly change to a song of my choosing simply by humming a few bars. All things considered, not such a terrible malady for a 90-year old reasonably healthy man. I am told there is no cure for my musical hallucinations and I am OK with that.