It seems to me that the first thing you should do before incorporating any of the good suggestions mentioned above is determine if you really have a problem that needs fixing. If you do not hear any hum, noise, hash, RFI or other anomalies during silent passages or with the volume turned up without a signal, spending the money on dedicated lines, power conditioners, regenerators, etc are all solutions to a problem you don't have.
J.Chip
J.Chip