I have what I believe is an unusual problem. I am sitting in my kitchen with 50% battery power left on my iPhone. I attempt to make a call with barely 1 bar of signal power and every call fails. I attach the sync cable to my computer as if I were going to sync and my signal bars go up to 3 & 4 and every call goes through. I haven't moved. Is it possible that a 50% batter is not enough to power the phone? Thanks for you help.