Customer reports an issue on ADV7612 that AVmute(IO map 0x65) is set if they swap the input port port-a <--> port-b by setting HDMI_PORT_SELECT HDMI map 0x00[2:0], meanwhile, there is only one port is connected and the other port leaves unconnected. It happens occasionally and only can be reproduced with their DVD player with 3D output, that means when DVD player set to 2D output it will be no problem.
We dump the ADV7612 register setting as attached, and found the AVMute is set. We tried to disable the "EN_BG_PORT_A" and "EN_BG_PORT_B" then the issue can be solved.
Can you please advise what's happened for this issue as if we disable the BG mode then the fastswitch function will also be disabled.