I have a 2002 grand prix my problem just started a couple days ago when i get up to about 30 mph I hear a humming noise, it does this in neutral also and stops at about 15 mph and idles fine any suggestions.i know this is a bonneville form just thought I would ask you guys thanks

It could be one of the hub assemblies. Does it sound like its coming from one of the tire area'* and makes a whurring or growling noise?

I agree. Typical symptom of a bad wheel hub.