Can't say that this is the fix or explanation, but in speaking with IT people I know, it may be that Pandora is using a lot of bandwith and effectively stealing it from my nook.
Check in your router settings if certain kinds of traffic have been given priority.
Perhaps streaming audio has been given too high a priority.
I have a Netgear N900 WNDR4500. I run Pandora all the time on my PC and never have problems with the NC. Others are streaming movies/shows at the same time. I can even stream movies to the NC from my NAS while others have the internet loaded. I have never seen a problem. Everything is wireless. Anyway, even if the router is bandwidth limited it should not lose connection. It will run slow. It sounds like you may have wireless speakers or headphones. They run at 2.4Ghz, the same as the router, so maybe it is causing interference. I would recommend switching the router to a different channel.