Ground Loop, Engine Noise

[Jackson_lmr]

Alright, so I’m having engine noise and static in the speakers. Here’s what I’ve done to attempt to fix it so far:
1. Power and ground straight from battery to head unit (grounded from back of head unit to battery negative)
2. Grounded rcas to back of head unit.
3. Checked grounds, all grounds measured 0 ohms (grounding bolt, distribution block, wires at amplifiers)
4. Replaced all RCA cables with high quality, triple shielded cables
5. RCA cables are ran on opposite side of vehicle from power, except the remote wire is ran with the RCA cables.

Just discovered, the noise gets worse when I unplug the rcas from the head unit

Any other ideas? The sound stops when I unplug the rca outputs from dsp to amplifiers.
This is my equipment: Pioneer DMH-1700NEX Head unit, Phoenix gold SX2 1200.1 and 800.4 amplifiers, and Phoenix Gold DSP.8.

 

[staan]

sound like its the dsp

 

[Bobbytwonames]

You might have to ground your RCA's.

 

[hispls]

The sound stops when I unplug the rca outputs from dsp to amplifiers.

Well, it's not the amplifiers then. Have you tried bypassing your DSP?