i know there was a thread going on about using earbuds which made me think of this problem:

went running the other day with the ipod and the next day it froze up on me. i researched how to reset it and it worked fine. though i hear if you run with an ipod it can really mess it up, no matter which one your using (nano, shuffle, whichever). i have a friend that went through 3 different ones and they all broke when he ran.

has anyone else run into this problem? i'm afraid to use it for running, indoors or out. if it is a normal problem is there a good mp3 player to use?