I've got a Samsung UHD Blu-ray player and a Virgin Tivo box plugged in to my Denon AV Amp. The output of this is then plugged in to the HDMI 1 input of the hub thing that then plugs in to the Television.
My problem is that when ever I switch the Tivo or Blu-ray player on, the sound will keep defaulting to TV Speaker. The Receiver option isn't availible from the sound output options and I have to unplug the HDMI cable from the Hub to get it to recognise the receiver again. The picture displays correctly so I know the feed from the blu-ray and tivo is working correctly.
Does this issue happen when the Denon AV Amp is connected via the HDMI ARC port? Have you tried another HDMI cable to rule out the cable being the issue?
It might also be worth getting in touch with Denon as there may be some settings adjustment on the Amp required.
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