Strange Sub Amp Issue
I have a 2 amp setup - Alpine 5 channel Theatre amp for front and MMats D1100.1 for dual 8" subs. When listening to music at LOW volumes, I hear the bass barely breaking through to the subs causing a very faint "farting" type sound. It almost seems like crosstalk. This issue corresponds to the beat of the music. When there is a kickdrum hit, I hear the faint fart/burp noise very faintly. At normal or louder volumes this does not happen. This happens with the engine on or off.
One thing that I can think of is that I have the 12v running down one side of the amplifier as space is limited. Generally I would have the power line approach the amp at a 90 degree angle. In this case I cannot.
Also, when the volume is turned down to "off" and I place my ear to the subs, I hear a faint engine noise (at least that what I believe it is) sound. With the car off, this noise is not present. This noise was louder before swapping from a standard shielded RCA cable to a homemade CAT5e RCA cable. The twisted pair cable eliminated some of the noise.
Any help would be greatly appreciated.