Well, I am not very technical but I did have to turn off HDMI CEC. I kept having sound go off, stay off a few minutes and come back, turning CEC off seems to have fixed that. So as far as ARC, all I know is the HDMI cable is connected Reciever ARC to Sony TV ARC. Looking in the Manual again, I see it should give me a message of “Check SP Wire” if there is a wire short or “AMP Diag Mode” if another issue, but nothing about “AMP Speaker”. I just thought maybe one of you Gurus on here might know. I am trying to find time to call Pioneer Tech Support. Thanks to all who commented.