Random volume fluctuations while driving

[BAM its mitch]

I drive a 2011 VW GTI with the premium Dynaudio sound system.  I am keeping the stock amplifier and speakers and only swapping out the head unit.

 

Here is what I have used.

Pioneer AVIC-X940BT

PAC RP4-VW11

Ground Loop isolators

ENFIG AAA-VWAUD5 (Don't actually have this yet, waiting for it in the mail)

Parking brake bypass via an additional wire inserted above the mute wire. This wire and the parking brake wire are both grounded.

 

From the headunit I have used the speaker level outputs with ground loop isolators wired in.

I added in the ground loop isolators because I had a white noise issue.  I guess some Bose units also have a similar issue due the amp ground being capacitive or something.

 

While waiting for my antenna adapter to arrive, I have been listening to Pandora via Bluetooth.  When driving, the sound will randomly fluctuate (not extreme fluctuations but definitely noticeable.)

 

1. I never experienced this with my stock headunit and the exact same phone.

 

2. All connections are properly soldered and heatshrinked.  I didn’t use any crimp connections, so I doubt that my wiring is the issue.  Plus I have looked it over multiple times and it will be looked over again when I wire in my antenna adapter.

 

3. It is my understanding that the X940BT doesn’t have ASL which seems to be the culprit with a lot of other units. Is there some other “feature†or “function†that could be to blame?

 

At this point, I am
clueless.  Help please?

 

*edit*

 

I have since tested, and determined that there is something along the lines of ASL that is changing the volume as speed increases.  I am unsure if it is actually based off of speed or an ambient noise mic.  I can't find any information about it.  If anyone can point me in the right direction, I would be very grateful.

[dgmorr]

I stopped reading when I saw you are using a PAC device. I am using a PAC TATO with my factory amp and the volume fluctuates as well.