Phone shuts off if bumped

[chrisb2e9]

Hi,
Twice today after sending a text my phone shut itself off. Not the screen, but 100% off.
I discovered that if the phone gets bumped, not even that hard, it will turn off. I thought that the battery might be loose but its in there pretty tightly.

I tried searching but can't find anyone else with this issue. Does anyone know if there are any connectors in the phone that are prone to coming loose?