I agree with Susan. That "error" sometimes happen to me when the disc is dirty or when the player was not leveled correctly. I tried vibrapods, sand bag on the top, inflatable inner tube, etc. At present I am using Star Sound audio points and Virtual Dynamics Power 1.
One thing I did (since I am using the analog output on mine) is to put a 75 Ohm resistor to a male RCA plug and terminate the unused 75 Ohm output port. To my mind, the player seems a little bit quieter. I did this after reading that noise in un-terminated digital source can contaminate the PS,thus making the unit (not particularly CD player) noisy.
Also, it seems that shielded cables sounds better to me in this particular cd player. I am using TS Premium from Odyssey Audio. I would also recommend to clean the lens (using Cdrom or DVD lens cleaner disc) every few months or as necessary.