The power button on my M424 is stuck and now wont

Try some sticky tape on it and pull up.

its down because theres a tiny rocker piece of plastic on the backside of the button that connects the button to a switch on the circuit board.
if you press it too hard or just from wear it gets bent. the only way to fix it is to disassemble the camera, take out the piece, warm it ups with a hair drier and put an arch back in it.