Had the same issue with my lg optimus pro on kit Kat just replaced that with lg g4 which updated to marshmallow and immediately upon pairing to my kenwood car stereo it started all over again... Did a factory reset and did not allow a restore of my apps/data thinking something from old phone got copied that caused it.. No dice still fighting it. Really wish a fix would come out... Didn't have the issue for the first year and a half I had the lg pro so this is definitely something new from kit Kat on up...