Hey guys,
I just recently installed the Dynavin head unit (replaced stock nav and DSP amp).
Setup:
'03 X5 4.4i
Dynavin head unit
Alpine 5 channel amp
Passive crossovers
I currently have an alternator whine (high pitch whine with rpm rise; revving the engine or accelerating during normal driving).
I've tried everything I can think of and researched on the internet; I'm out of ideas =(
- made sure all unused plugs taped up with electrical tape
- toggled the "Brake" option in the Dynavin settings menu
- grounded the "Park" wire on the Fakra cable
- grounded the Fakra ground cable (black wire) directly to a metal piece in the vehicle (also tried grounding to the same bolt as the amp's ground wire)
- adjusted the gain down on the aftermarket amp (helps make it less obvious, but still there)
- pulled all the RCA cables (Streetwires twisted pair) from under the carpet floor and had it running straight through the interior cabin from the head unit to the amp
- installed a ground loop isolator (also helps make it less obvious, but still there)
- cut the amp ground cable to the bare minimum
- used a dremel to sand down the contact point where I bolted the amp ground cable to a medal piece in the vehicle
- installed a power line filter on the yellow wire of the Fakra cable closest to the plug into the head unit
- cut all of the FL/FR/RL/RR audio cable line outs in the Fakra and taped them up individually (using RCA output only)
- used the shorter harness to connect the head unit directly in the trunk and running a short regular RCA to the amp
I had the head unit and amp on and RCA wires disconnected = no alternator whine. Plugged the RCA cable to the amp, but disconnected from the head unit, amp and head unit turned on = no alternator whine. Plugged the RCA cable into the head unit and head unit and amp turned on = yes alternator whine.
At this point, I am pretty sure I can rule out the passive crossovers, Alpine amp, RCA wires, and Fakra cable. Unless there's anything else I can try, the only thing left is the Dynavin head unit (head unit itself, or all the RCA output plugs). Do you think it could be a problem with the Dynavin unit itself?