I have just bought a Panasonic TX-55EZ950 high-end OLED TV, it's been released this early summer, so very new.
I have a Yamaha RX-A 2030 from 2013, it can read DD+ contents without issues through HDMI, never had an issue... until I needed ARC.
My use case: I want to use the Netflix app from the TV and only this one. As my amp is not HDCP2.2 it seems that all 4k image signals from Netflix cannot go through my amp (or maybe for another reason but it does not affect my ARC problem, I guess) so I can't use Netflix from PS4 Pro etc. unless I'm ok with 1080p only.
When I launch Netflix from the TV, I can select any of the proposed 2.0 / 5.1 audio options for any series. However, although I have absolutely no problem with stereo contents, everytime I switch to 5.1 sources (and they are the ones by default), my amp either act like no signal (decoder off) is received OR reads a DD+ signal for a few seconds then cuts audio (decoder off). Sometimes it goes on and off, alternating between decoder off >> dd+ >> decoder off >> dd+ etc.
I tried all possible options from the TV. All behaviours described above are with sound set to automatic. When set to PCM, decoder is off and never reads a signal.
Yesterday night something weird occured. The netflix app crashed and the TV auto rebooted itself. after this DD+ signals from Netflix were working great!
Then I turned the TV off, my Yamaha off as well. Turned everything back to on and... the problem came back (and is still here).
I tried with different HDMI (High Speed ARC approved) cables.
It's hard for me to test with a different amp so what would you suggest me to do? I thought about asking Panasonic but I am quite confident they will tell me it's the amp or the Netflix app or I should update to the last firmware etc. and I feel like I will lose a lot of time as this is a very specific issue.
One happy end for me would be that my Yam RXA2030 is too old to deal with DD+ ARC.