So after firmware and software updates and rebooting:
Hitting suspend on the 4900 used to shut down the box (red light) and HDMI switch to other active input (cable) All fine and dandy
Now it darkens the screen to black, (blue light stays on) then tires to switch to the other HDMI input, does so for a sec or two, then switches back. Try again, same. Box won't go red for approx 1+ hour if manually switched to other HDMI input