Replying to IPOD and GIRO Tune-up problems

Hey I got an Ipod for christmas and I just got the Giro Tune-Ups put on my helmet. I used them together for the first time the other day. When inside the whole thing sounded great, but after the first run things started messing up. The song would get very quiet and then loud, and you could hear the background music very clearly but the singing was very faint. It was not even that cold, maybe 20 degrees. Does anyone know of any problems with IPods freezing or defects with the Giro tune-ups? I have a feeling that it might be the giro headphones since I have used the Ipod in semi cold weather. Let me know if anyone has had this same problem. Thanks!