My question again. My father has just started hearing music playing, real low & the same song over & over. All day but mostly at night.

Lealonnie is right. I have it. I have developed some hearing loss in my left ear and this is when it started. It is truly strange. My bedroom is right next to the furnace closet. I only hear the music when the furnace is on. It’s like a radio station. I “hear” people talking, what sounds like commercials, and once, on New Year’s Eve, I heard Auld Lang Syne! It’s very annoying. I’ve even listened at the door of the closet when the furnace was on and heard nothing. It’s inside my head. You can explain to him that this annoying issue is just that...annoying. Share my experience with him if you want.

It's called "Musical Ear Syndrome", I believe, and it is NOT dementia related, but hearing related: https://www.ncbi.nlm.nih.gov/pmc/articles/PMC5353248/

Musical ear syndrome (MES) is a condition that causes patients with hearing impairment to have non-psychiatric auditory hallucinations. ... Hallucinations are usually musical in nature and can range from popular music, orchestral symphonies, or radio tunes.

Best of luck!

Someone recently posted about this and I wish I could remember the name of what this is called. It is, yes, an actual syndrome. Do go to google or another search engine and type in "dementia and hearing music that isn't there" or any phrase similar, and I hope the person who informed us the first time is still on forum and reading and will respond again. Dr Oliver Sacks before his death wrote extensively about music and the demented brain in "Musicophilia" and explained how things such as music can become stuck in a replaying loop in the demented brain. I recommend his writings on Dementia overall for some of the most profound things out there. He saw the brain as active and intriquing, and dementia not so much diseased as differing. Some of the most interesting things in brain research came through his lifelong work on the brain.