HDMI signal cuts out for a few seconds constantly from receiver to television. It does it when switched to cable box and the roku box. Onkyo TX-SR606 Scientific Atlanta Cable box thru HDMI Roku Box Thru HDMI

Mine did the same thing where the screen would go black for a few seconds and then the picture and sound came back. I would try (1) switch HDMI cables, (2) try a different HDMI input in the back of the receiver, (3) try different input in the back of the TV. None of these seemed to work with mine. I finally ended up running the cable box direct to the TV and only run the audio through the reciever via coax or digital. No more problems. I think the HDMI inputs in the back of the reciever have a problem continuously carrying the signal if it is the leaset bit weak.

I have the same sort of drop out of both audio and video, but only from Sat-alight receiver to SONY home theater receiver. Drop out occurs when switch mode appliance in the home is turned on. Noted when satellite receiver was being swapped, that its chassis was live, tech said it was to do with 16 volt supply up to dish. Your solution would give the two units a common earth to both ends of HDMI cable. Thank you for a valuable clue.