Does the Sprint LG Rumor Touch use 3G memory while in the music player?

Just wondering because I don't want to run up my bill.Does the Sprint LG Rumor Touch use 3G memory while in the music player?
Yea it does, I got hit with a HUGE bill that I couldn't figure out. Finally, after talking on the phone with Sprint for a while, I found out it was the music player, which doesn't make sense to me. Anyway, be careful, I almost died when I saw that bill.