Ok, you didn't provide much information such as how old your components are, how many hours on the tubes, how old is the cartridge, was it set up properly, etc. If this is a new and unchanging occurrence, I agree that mis-tracking is the most probable cause and a great place to start looking. The easiest way is to simply try another source and see if you still get the noise. Once you rule that out, consider tube replacement. Good luck!