Quick question about the computer in a 2003 Volvo S60

[DG26]

Okay so I am trying to figure out what this squeaking is, and no one has said anything in my other thread, so I'll make this one.

So I unscrewed one of the bottom flaps where the pedals are, and when I did this the computer of the car came falling down, is this computer supposed to be bolted down somewhere? I had someone install my sound system into my car, could they have got lazy and not bolted it back down, that is if they even messed with it? Because after I got this sound system installed the squeaking had got pretty bad near the steering wheel, when I hit bumpy roads.

So could this be the reason why it squeaks, is this computer supposed to be bolted down somewhere, and not just hanging loose?

Or could it still be something else?

Any ideas, and comments are very much appreciated, I wanna get this fixed soon, it's annoying the crap out of me.