Trying to get rid of engine hum??

[khisanthax]

I have a lot of rca cables running to and from an av switch I have in the trunk. WHen I try to get my devices through to the main HU and speakers I get a lot of hum. I bought a grounding loop/noise filter and it reduces the hum but it also reduces the volume of the connected devices by about 50%.

Is that the only way to reduce hum? Can the engine hum and noise be caused by several devices sharing the same 12v source or ground source?

[frankenberrie]

Do you have the RCA cables running next to your AMP power cable? That could be causing electrical interference

[khisanthax]

no, lol, no amp yet. I grounded the important stuff so that each had it's own ground ... and narrowed it down to my av switcher which is making the hum ..... anyone know of a good av switcher? 4x4?