Still seems like you didn't properly check the function switch, which would be first on my list.
An improper wire connection, as docs said, would be the second.
Try using a compressed air can upside down on the boards and on the components, little areas at the time, while the radio is on. This will create iced spots which may engage a lost connection somewhere, and may pop up the sound for a moment. This might help figuring out where the issue is coming from.
An improper wire connection, as docs said, would be the second.
Try using a compressed air can upside down on the boards and on the components, little areas at the time, while the radio is on. This will create iced spots which may engage a lost connection somewhere, and may pop up the sound for a moment. This might help figuring out where the issue is coming from.