new to this,need help

i have a parasound preamp,proton tuner,cd and proton amp stacked on top of each other in that order. (preamp on bottom) all new. the first problem i had was a very low hum in the system. i tried another outlet and this went away. now for the second problem, i first turn on the preamp, then the problems or sounds. when i then turn on the tuner, even though i have cd selected on the preamp, i can hear very faint radio signals coming through the speakers. what's going on? i also get a very low hum when i turn on the cd, but i assume this is because i have a cheap cd, am i on the right track. also could someone suggest an acceptable cd player. thanks very much.
Hey there new audio person! Lots of reasons for hum/radio signal (poorly shielded interconnects, ground loop, poorly buffered preamp, etc.). The key words here (in your note) are: "All new". Know what this means? It means you can go to your friendly dealer" with this and get free help! Cool huh? Good Luck!
bought the tuner and amp six years ago,never used until now,dealer out of business, bought the preamp online,old cd i'm on my own, not so cool, huh?
Have you tried unstacking your components, try it, or just put something like a book in between them to separate them a little. It is usually a proximity thing.