After driving into work, my iPod worked perfectly, until I stepped outside. The temps were about 45 degrees Fahrenheit, and suddenly my iPod just locked up. It wouldn't work until I got into my building and it took it about 45 seconds to warm up again then started playing. My walk from truck to building is about 2 - 3 minutes. Any ideas on how to keep the iPod warm enough to keep working when it is colder outside?