Have you cleaned the cart and the system?
Have you cleaned the cart and the system?
How did you clean it?
Please open the cart and clean the contacts with, at minimum, an eraser until they look completely clean. If you can get some de-oxit, that would be a great finishing move after the eraser.
I had similar problems with my copy and this did the trick. If the basic isopropyl + Q-tip doesn't work, always open the cart for a more thorough inspection and cleaning.