@djlogix does your Bluetooth device have ground loop noise? I don't want to say it doesn't need one because I haven't tested it on a Car, it probably be a good idea to have but with the wall AC and batteries is OK It does not, all test with all devices is dead silince It might just be the step down transformer i'm using that is causing all the noise. I'll look into find a unit that can use 12v to test. Hello , I use this https://www.amazon.de/Wuiyepo-Bluetooth-Decoder-Board-Wireless/dp/B01CJI1Q58/ref=sr_1_7?ie=UTF8&qid=1480597944&sr=8-7&keywords=MP3+Decoder and have the noise too.
