I`ll disreguard the amp..I`m FCC licensed, so I cant comment if its hooked to a cb.
If its hooked to a stereo, I can
go to (walmart/kmart/radioshack) and buy a powered noise filter for car stereos- something in the 200-500watt range that has both power and ground in/out.
Run the power from the battery to the filter, from the filter to the amp(if on stereo
)- ground the filter, use the ground from the filter to the amp(if on stereo
) and your good to go.
when I ran my cb, my ham FM, and the radio/amp combo- there was a howl from the alternator that I just couldnt isolate. Thinking back to my install days, we had bosch filters-12volt- that we always used. Found a similer one a wallyworld-sosche- for $19.00. As long as you dont exceed the wattage of the filter, it makes things pretty quiet. The CB recieve seems a bit furthur off though...takes a bit more incomeing signal to pop the limit. It did completely cure the alternator whine.