Would you mind too much verifying that the Octava acts as a sink even after you turn everything off and back on? How about if you just have the Octava run the PS3 with no other HDMI devices in the switch?
Yes, that works. After disabling the auto scan feature on the Octava, the unit just stays on, even if all sources and monitors are turned off. You can just insert a (SA)CD into the PS3 and it will play.
Just to be clear, my plasma screen is connected to the Octava, but turned off (standby actually). I do not know whether it will make a difference if I really disconnect the plasma from the Octava.