Newbee; I agree with Atmasphere on this. If you unplug and disconnect every piece of equipment and then plug in the Amp to the speakers and turn it on and no noise. then plug in the pre-amp to the amp and no noise. Then plug in the CD player and there is noise. First thing I would suspect is a faulty ground scheme in the CD player. But before I replace it I would try other interconnect cables. the ones you are using from the CD player to the pre-amp may not be shielded properly or the shield may be tied to the signal ground. If you still have noise, then just for fun, plug in a different CD player or DVD player to the same input on the pre-amp. Noise? No? then your CD player has issues. Yes? Then it may actually be the pre-amp's internal ground scheme. But, I believe that it will be the CD player or the interconnect cables. If you try all that, then try this. Plug all you low level devices, Pre-amp, CD players, TT, etc. into the same conditioner device. Then plug your amp into the wall outlet. typically with all the low level devices connected together and the amp plugged into its own wall outlet (hopefully a dedicated line to the circuit breaker panel), not only will your noise floor drop significantly, but ground loops disappear.
Try it.
enjoy
Try it.
enjoy