I'm not getting audio signal on DVD (HDMI2) or ROKU (Game/HDMI3), including on headphone jack. Video is working, but no audio. 5.1 audio working fine for cable box (optical cable). Input designations appear to be correct in 750 set-up menu. Is it possible that 2 HDMI cables could be bad? FYI, I did recently replace my multi-channel amp when multiple channels went out. I suspect a power surge was responsible. New amp (Outlaw 5 channel) is working great in 5.1 TV mode.