I was assuming it was the battery dying since it doesn't do it while plugged in but surely if the battery was running down quickly then it'd show that on the battery symbol... Wouldn't it?!
Contract runs until October but the battery is only covered for the first of the 2 years. Is it likely to be the battery, despite it never saying that it's getting low before turning off? I don't want to waste money buying a new battery if that's not the problem!