Agree with the above. The problem here is the machine you are using, basically it's a budget/ dictation machine and totally unsuited to music recording. What you need is a
tape deck, this connects to an amp and will have far superior performance. Dual well decks from the 1990s are fairly cheap and you can also copy tape to tape, probably a good place to start. Bear in mind any deck that has not been recently serviced will need a new set of drive belts by now. Try before you buy if possible.