So apart from some LCD issues, my Pre lately has been doing something strange which I can't figure out the cause to, wondering if anyone had any insight.

Basically I'll have like a 60% or > charge and the phone just turns off, mind you it is just sitting on a desk. No bumps, drops, anything... it just turns off. Now the weird thing is, when I hold the power button nothing happens. It isn't until I pull the battery out, put it back in, and then hold the power button does the Pre turn on.

I am trying to get this replaced via sprint under my warranty because of LCD issues but they gave me the run around on that, and now it is having this issue... Has anyone else experienced this? if so what could be causing it?