Can Wireless Signals Affect Audio Quality

Doubt it.
My roomate has a wireless router setup going, i never noticed any difference in quality of sound when it is on vs off.
I would be more worried about any hum from the router interferring with my listening.

I've got one set up in the same room as my system, and I have noticed no problems at all.
Rich

I don't notice any problems from my wireless pc network. I do notice when my wife is on the cordless phone. Like between songs, you can hear this kind of quite buzzing sound. It changes as she walks around in the rooms above my basement listening room.