Sub, mabye amp issue

[skylakaylah]

My car has a 4 channel amp where i run my front speakers and amp though. Lately, the sub cuts in and out (seems like it happens when i hit bumps) I got a car place check connection and they reckon my amp was faulty, so i get a new amp and problem is still not fixed.

Fuses are fine. Connections to amp are fine. Got one of those alitmeters out and it seems like amp is only getting a small amount of power.

Any ideas? Thanks

[PaulD]

chech the connections where the the fuse holder is, the fuse may also be mostly blown

[cramer_77]

check the continuity of your power wire, just do a simple ohms resistance test, thats where i would check, also you might check your ground, you wouldn't believe what a bad ground connection would do.