Over the weekend I installed a Clarion HU VX400 into the titan. I have an SE 2005 and replaced the RF head unit and left the RF amp. It is hooked up via the RCA of the Clarion into the Titan specific harnass. The new unit is great and works perfectly...however, when I switch sources or when the turn the unit on or off there is a LOUD pop from all speakers, not just the sub. Crutchfield says it is a grounding issue. I cannot live with this pop everytime I change sources, or the phone hooks up via bluetooth. I have searched the internet for the past 3 days and cannot see a specific discussion on a Titan. I tried to 1) power the RF amp without the remote amp turn on in the Clarion 2) tried to power it with a 5v power supply, 3) tried to ground the unit in 3 different places. Nothing has made a difference. Some forums have suggested a 100-120ohm resistor between the harnass and the power amp on on the Clarion but this obliously won't work for me sicne the other things I have done did not help (that being bypassing that power source althogether). I cannot be the first person to have this problem. I have searched everywhere for an answer. Anyone know the problem or a possible solution. Anyone....