I have experienced the same problems with my 60 cs, right after I bought it. It just turned it self of, no matter how much battery capacety that was left... To fix it, I just put some cardboard paper under the contakts. I bought my 60 cs the same month as Garmin launcht it, and its been working ekstremely well ever since my fix. I use it a loot for long hikes, kano traveling, skiing etc. (And as a toy for my 2,5 year old daughter.) The power is working as i should, after that little fix. I met a couple of other 60 cs (x) users that experienced the same problems over the years, this fix always solves the problem.