RobNBill

You can download it - see AVS Forum Post: AVS Forum Post with Download Link:  

05.10.15 works for me.: Apple TV 4K (Second Edition) >> Denon X3300 >> LG C9. DV works again - no flashing, black screens, etc. You may want to check for a Denon firmware update. A day or two after this problem occurred I received an OTA FW upgrade for my Denon. There is a post in the AVS Forum that some AVR's may need a FW upgrade too. Mine worked immediately after I updated the TV.

See this thread: https://www.lgwebos.com/topic/7206-c9-update-051004-can-no-longer-connect-to-dolby/ LG has issued 05.10.15 to address this issue.

I found this on a German website: LG-OLED-TVs B9, C9, E9 und W9: Fix für Dolby Vision in Arbeit I have no idea how credible they are. In part, from Google Translate: Since the beginning of June, LG has been distributing firmware version 05.10.04 for OLED televisions of the 2019 generation, i.e. for the B9, C9, E9 and W9 series. The firmware causes an error in interaction with AV receivers, connected players and the HDR format Dolby Vision, which leads to strong image flickering. When asked by heise online, LG stated that the error is known and that another firmware update for the affected OLED TVs with a fix is expected to appear next Monday, June 28, 2021.

If I connect directly from the ATV4 to the LG - DV works fine. Also, if I connect thru the Denon when it is in standby (Apple video is set as a pass thru to LG) DV works fine. It's only when the Denon is on do I have an issue.

You may want to check this user post in the AVSFORUM: https://www.avsforum.com/threads/official-2019-lg-c9-consolidated-info-faq-troubleshooting-firmware-more.3075344/post-60821868 He said in a previous post LG is aware of the issues and is testing a fix now: https://www.avsforum.com/threads/official-2019-lg-c9-consolidated-info-faq-troubleshooting-firmware-more.3075344/post-60821823 The above user is credible. FWIW: When we started up our ATV4 > Denon > LG C9 system last night we were offered an update to an older Denon AVR-X3300W. Firmware Version: 8700-4058-9140. I updated to that version. There was no information as to what was in it. I suspect this is Denon's fix on their side. Waiting now for LG's fix.

Hi - Is your Sony output Dolby?

On the Denon, if you enable "Pass Through" of the ATV while in standby mode - you can select Dolby on the ATV and the C9 accepts. Guessing LG made a change that affects HDMI communication with the Denon since it was working fine immediately prior to the update. I have a ticket open with LG - they said their sofware enginners would get back in a couple of days. If I get a resposne i'll post it here.

My issue occurs only when running the HDMI thru my Denon AVR. If run direct it works in Dolby.

Since this update the Apple TV 4K can no longer connect to Dolby via HDMI. Immediately prior to this update - it worked. Now, if you attempot to connect and set it to Dolby - the screen flashes the Apple TV screen on and off - it can't stabilze. This happened immdeiately after the update. Can I revert back to the prior software? Or, can you send me a version that does not have this issue.