Fuse Box?????

2003 Malibu there is a box under the hood full of fuses and relays on my malibu this box is very loose. should this be tight??
the reason for asking sometimes when we hit a bump or speed bump or such the radio statics and the door lock and unlock 6 or eight times then the car will shut down.
I think it is losing power suddenly and then right back but just enought o shut the system down causing us to have to restart. any think this sounds logical??