You probably have the wrong firmware on it. The headphone jack was replaced on the model and they reversed the polarities of the jack. As a result they had to add a second firmware that works for the new switch. Search the GPD site and get the other version of the firmware you have now. You should also consider getting CleanRom. This is a custom firmware for the XD+. Once installed the fix is just a toggle. Once toggled you are done.