I listen to my system every night while my wife usually sits in the chair next to me and surfs the web on her phone. Romantic eh?. She has gone away on a vacation to visit her son who is on a military base for a week. So last night as I was powering everything up and I noticed the lights from the modem and the router and thought I don't need these on until she returns, so I un-plugged them. As I started hearing the music, I couldn't help but notice the system sounded way WAY better. As if I had up-graded to better IC's or put in a better tube in the MC225. The modem and router are on 24/7 and so I've never heard the system without them being on until last night. I do have a dedicated power line to the amp, but turning off the modem and router was a substantial improvement without any doubt. I have learned so much in this hobby buy experimenting and trying different things to improve the sound. Some of the things I have learned from different sources are; Keep the AC plugs clean and polished, with no tarnish Keep florescent lights off. Un-plug all phone chargers And now I've added, turn off modems and routers. I suppose I could spend a ton of money for a power conditioner, but I don't have the space or the money, so I'll just keep these things off. Try it and see for yourself.