So it looks like I have the 1.4 revision of the B+ from 2023. I tried a few other fws, including the oldest one I could find that will boot, which is from 2021-10-30 found here https://downloads.raspberrypi.com/raspios_lite_a…mhf-2021-11-08/
and I still get a slideshow on most 3D MVC videos 
Looks like I just wasted my money and will have to go back to using the 3B
It was even easier than I thought:
- Image the MicroSD with v12
- Copy the bootcode.bin, fixup.dat & start.elf files to my PC
- Image it again with LibreELEC-RPi2.arm-9.2.8.img
- Overwrite those files on the MicroSD before putting it in the RPi
- Boot as normal to 9.2.8That's it! Thanks for letting me know about firmware rev!
Ha, I didn't see your reply until after posting. Thanks so much Hias - As always, it's much appreciated!
Are 3D movies playing ok for you? I was using an RPi 3B before and it was working great, saw your article and thought I'd grab an RPi 3B+ for the faster network speeds. Almost all of my movies play for a few seconds and than freeze, updating a frame every few seconds. I originally tried the fw files on your article because it wouldn't boot with the original fw files and then I tried the files from the very latest v12, which seemed slightly better, but still having issues on most of my movies.
Interestingly, my RPi3 B has the same freezing issues when using new fw files, but is perfect with the original fw files that came with 9.2.8.
Wondering if there are FW files that will work properly with my RPi 3B+
Display MoreWhy don’t you use your AVR?
If you have your TV connected through ARC means it’s 2 way traffic.
Just looked at specs of your AVR and it had hdmi 2.0 support.
I run a LG 4K TV to a Denon AVR and on these inputs are my PS PRO, and my Kodi box.
When I switch to movies on kodi, my AVR goes to the mediaplayer input, the audio is set to whatever passthrough the movie has, and every setting is possible, and sends the 4K (HDR) signal to tv. Same with my PS Pro.
Just activate HDR on your tv on the hdmi port that runs to your AVR and when possible, set your AVR settings to HdMI advanced. This os only when you have HDR compatible stuff.
Your AVR is you hdmi hub/switch
How do you have this all set up?
I have a 65" LG C7 OLED and a Denon x2400h and have no end of issues with HDMI-CEC, I'm considering turning it all off completely.
Every time I switch my AVR or TV, or switch back to HDMI 2 on the TV on it switches the AVR to the Kodi player input. If I disable CEC on the Kodi player then it always switches to my Chromecast. I have everything connected to the AVR and then to my TV on HDMI2 with ARC turned on. I have no audio issues, just lots of auto switching issues.
It's annoying because if I use my phone to start playing from my chromecast the TV and AVR automatically turn on, but then after a few seconds it switches to the Kodi box.
