I need help with hum

Moved into a new apartment. Despite the Cinepro line conditioner I am getting a BRUTAL hum throughout the system. Problem persists even if I direct wire cd player through amps skiping all other components??? Is this a power problem? A Ground problem? Is there a cost effective solution?
First step - disconnect the cable TV wire from everything and unplug that cable box.
I had a bad hum not too long ago. I have a tube amp connected to a TV. I got a 3 prong to 2 adapter which removed the ground from my amp. Bingo. I am using a surge protector.
I concurr with the above posts.
Going from 3 prong to 2 prong reduced hum from my turntable/MC/pre-preamp. Connecting cable TV via VCR caused terrible hum that disappeared when the cable was disconnected. I have heard of units that can block the cable hum but I have no experience with them.