How to get a good ground

NorthStyle

It the tablet that is the source of the noise, specifically the 3.5mm headphone output. Use a DAC to pull digital audio from the USB port and the noise will disappear. You will have to run a OTG hub with the proper cable for it to use audio while still charging your tablet.

1/4atatime

This is the answer I was only able to get about 30% of the noise to go away on my brainiac kit even running to different power than the stock radio and adding a noise supressor on top of the rca noise isolator. Added a dap (dac and music player combo) it went down to only 10% static. Bought another dap with a very high SNR and a car mode and boom problem fixed. I get some very slight hissing but it's hardly noticable unless I'm paying attention especially not over my exhaust. There is some really terrible grounding in tablet audio chips. Buy a Fiio BTR5 and you should be good (even has car mode to power on and off when it detects power changes) https://www.fiio.com/btr5

The 370z and the grounding in that kit when hooked into a tablet just does not play nice. I talked with that guy who built it and he said some of our cars just have problems with it and Nissan did something inside the radio to remove the grounding issue. So even on some aftermarket radios you get problems.

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