Decided to start a new thread covering issues with this new firmware since the 7.7 thread turned into a mess.
Got the update last night and it still hasn't solved the issue I am having with the screen flickering and sometimes giving HDCP errors. I can temporarily solve it by unplugging the HDMI cable from the ROKU Ultra or the receiver (in sig) waiting a bit then plugging it back in or the better way is to switch inputs on the receiver (again in sig) wait a bit then switch back to the Roku input. I may have to switch it back and forth a few times but after that it settles down and gives me no more problems until I either switch inputs and watch something else or turn off all the equipment then later try to watch the Roku again.
I switched to the 4:2:2 setting on the Roku since the 4:2:0 setting is much less stable. If on 4:2:0 I can never really get it to settle down with the flashing even after switching inputs or unplugging the HDMI cable. Before the 7.7 disaster I had no problems like this. I could set it to either 4:2:0 or 4:2:2 with no issue. I didn't get any flickering or HDCP errors either.
This is happening on every channel, main screen, etc. Turning off HDR did not help. Turning off HDMI control did not help. Setting audio to stereo did not help.
Everything else seems to work ok, hopefully Roku takes this seriously and fixes it, it's very annoying.