Static in Double Din Stereo Unit

I recently installed an aftermarket Android based navigation/stereo double din in my vehicle. I have a 2002 camry with JBL. I am using this wiring harness from Metra. Everything works well with the exception of a low static that is present on all speakers. When the unit is power off the static goes away so I am positive its coming from the unit.

• I tried buying 2x ground loop isolators from BestBuy. I put them on the output RCA connectors for the 4 speakers. It seemed to have no effect. When I installed them I connected the brown wire named ground to a black wire named ground on the metra harness.
• I tried attaching a wire to the double din case and to ground. It didn’t work.
• One thing I did notice is that the navigation/stereo unit has a black called chassis ground. The Metra cable has a black wire called ground and a black/white wire called amp ground. I tried tying them all together but it didn’t help.

The sound is fairly low but definitely audible in fact I have been driving with the unit turned off as of late to avoid the sound. People with a touch of tinnitus can’t seem to differentiate it. At this point the only solution I can come up with is to wait until I grow old and develop tinnitus myself.

I’m wondering what else I can do to troubleshoot this issue? I was considering going to BestBuy and buying another unit to see if the problem is with the vehicle or the head unit. Another option I wanted to try is to connect the head unit to the physical vehicle chassis but I’m not sure what on the car is consider the chassis.