There are usually karaoke specialty shops in major cities. These are good places to purchase music and sometimes equipment. You can also order rare music from the internet. Some people have had success borrowing a friend’s collection and making compilation CDs.
I suggest hiding a switch in the closet that turns the machine off. “What’s the matter, dear? Oh, the machine’s not working? It must be overheating. Let’s give it a rest for a few hours.”