Well, for me the CEC problem has a solution somehow strange. I have Q5, bluray (both in Yamaha receiver on hdmi 2/hdmi 1) ans Samsung with ARC.
If I start TV and receiver I have no ARC from TV to receiver, unless I start Q5.
If I start Q5 and receiver/TV I have no sound from q5 (receiver started on hdmi2) unless I chenge receiver to hdmi 1 and again on hdmi 2/
If I start bluray, receiver, TV I have no control to sound from TV remote unless I start Q5...
It will be great if CEC could be disabled from Q5 settings, otherwise looun's solution (to cut pin 13) is best...