Tesla Screen hissing noise

makeao

Hey,

I got a tesla screen for my 2019 Nismo from Nifty City.

The screen is working pretty well but im getting a hissing noise coming from the speakers, it turns off when volume is on zero, and does not increase with rpm or music volume, so it's only noticeable at low volume.

The screen comes with an "audio decoder box" which places in between car harness and screen harness, this things removes the hissing noise but aswell a lot of the volume of the bose system (which I was happy with).

Any idea on from where this hissing noise can be coming from? I grounded the screen to the center point behind head unit. Also tesla screen have an option to "bypass factory amp", which is giving me better sound volume, but not as good as prior to install. (And I dont know how it bypass the AMP, since speakers are wired to bose amp, right?).

At this moment Im waiting for a response from nifty city, to see if they know specs of outputs from the screen to bose AMP, to start with.

Any ideas to get rid of the noise without using that box and lose like 40% of the volume?