Yesterday I was out riding on my motorcycle with my Karma as I have done several times before. It played no problems for about 2 1/2 hours straight, turned it off for lunch, and after lunch it played fine for an hour until all of a sudden it just stopped playing mid-song. This was just before a scheduled stop, so I pulled the Karma out of my pocket and it showed as playing but wasn't. I tried the riostick to see if it did anything and after a while it did, but still wasn't playing, so I tried to just turn it off, but it sat there for quite a while with the hourglass spinning. After far longer than it normally takes to turn off I got worried and found something to push the reset button. I turned it back on and it started playing a few songs back from where it was at. It played fine for 45 minutes and then stopped playing but I couldn't easily pull over to check on it and it started playing again after about 2 minutes. The same thing happened 15 minutes later and 10 minutes after that I pulled over and the battery was at about 10% so I turned it off.
It is playing fine so far this morning but lately I have been getting momentary breaks of less than a second, kind of like a CD skip which I'm pretty sure aren't a problem with the MP3.

I have firmware 1.68 and a little over 18GB on the player.