Hi. I have a Raspberry Pi 4 on which 9.x.x has been running beautifully for a long time. For various reasons, I'm trying to upgrade to 11.0.0, but am not having much luck. I write the image to a flash card (using the Raspberry Pi Imager) and then attempt to boot, but:
- The display shows a message indicating there's no HDMI signal. (It flickers a couple of times during boot, indicating that there might briefly be a signal, but it never stays for more than a moment.)
- If I move the HDMI cable to the other output on the Pi (i.e. the one that I wasn't using with 9.x.x), I do get a signal, but the screen is mostly black, with the message "LibreElec 11.0.0" in white at the top left, which never changes.
- The Pi responds to pings on its IP address, but I cannot ssh to it (perhaps ssh is not set up?) and Kore can't see it.
- There's no obvious response to keyboard or mouse.
Some other details:
- I've tried with a couple of different displays, with much the same results.
- Unlike this issue, disconnecting/reconnecting the HDMI cable doesn't help.
- Unlike this issue, I don't see any of the normal boot screens, and using a different display makes no difference (same results).
- In case it's relevant, the Pi has an "official" PoE (power-over-ethernet) hat, though the same issue happens whether the Pi is powered by PoE or directly.
- The displays I've tried are all 1080p resolution.
- A few months ago I did try upgrading to 10.0.2, but had similar issues (though at the time I didn't investigate much further and simply reverted to 9.x.x).
Clearly other people are using this release with Raspberry Pi 4 devices successfully, so I must be doing something wrong. I'm at a bit of a loss what to try, though:
- Since there's no display, I can't easily extract logs. Are there useful logs stored on the SD card somewhere that I could get off eg with another Linux machine?
- Does anyone have any suggestions of what I might try in order to fix the problem, or at least further diagnose what the issue is? With keyboard, mouse, ssh and Kore not responding I guess I'd have to modify things on the SD card?
Grateful for any suggestions and advice 
Thanks, Patrick
