does the noise change with the speed of the engine or is it a constant static?
Do this test..
Turn everything on with the motor running and so that you can hear the noise loud and clear.
Then un screw the CB antenna..
Does the noise go away, or is it still present..
It the noise goes away, then you have a much harder problem to solve.
It either the problem is in your antenna or in the car..
It may have bad plugs or plug wires.It is receievin gthe enterference through the antenna.
If the noise is still present without the Antenna, then the noise is coming through the power..
Depending on what kind of noise it is will determing what kind or filter you need.
An alternator whine changes with the speed of the engine and is high pitched.