Sharp Qt-5 cassette has low sound/plays static

Hi everyone, I just bought my dream boombox on ebay, a sharp qt-5 in green. The seller said the radio works great and is loud and clear but the cassette player has low sound/plays static. I was wondering if its a quick fix like cleaning it/demagnetizing it or if it's a more complicated issue. I won't have it until next week as it's in the mail, but I figured it wouldn't hurt to ask early! Thanks

Rebelt, clean heads, contact spray all pots, switches, sockets, reassess.

Ok an update! The ac adapter doesn’t connect well and I don’t think the player is getting enough power. I turned the ac adapter a certain way and had the cassette player working totally fine! Now of course I can’t get the ac adapter to work at all haha. I’m going to attempt to try running it on batteries tomorrow. Pretty sure it’s a power supply issue but not sure!