Audio Systems: Alpine 7179 problem, fuse block, bump in the road

Question
I bought a 91 Eldorado with an Alpine 7179 stereo. When I hit a bump in the road the volume changes. It is now to the point were I have to turn it all the way up to hear anything, but the static makes it unbearable to listen to it this way. If I jiggle the unit the sound improves but then goes back to no good! I suspect the connection is the problem but I do not know what to look for or how to repair it. Any advice?
Thanks in advance,
Bill.

Answer
Bill,

  first thing pull the unit out make sure the harness plug is connected securly into the harness adapter and if the splices are still connected tightly and insulated with electrical tape .. if they arent undo the wires one at a time and splice them back and wrap with tape... this should fix the problem if its in the harness.. this is where i think the problem is since you said you can move the unit and the sound improves .. but some other things to look at would be clean your battery and alternator terminals make sure they are clean also check you grounds and clean them up.. and check your fuse block for any loose fuses or any problematic areas... now these are the easiest fixes .. if these dont work then more than likly the unit has a loose ground or hardware inside which boils down to a replacement with a new unit..hope this helps you out if you need anything else let me know

thanks