So, I’ve got the mirror rebuilt and it’s working really well.
I haven’t gone near the PIR sensor yet, but plan to back up the SD Card in the state I have it now and come back to it if needed.
In short, I have the standard modules working in a portrait rotated position running on the official KMS OpenGL driver and it’s transitioning smoothly and without the glitching.

One thing that has occurred to me, during my first build I was using the overscan_left=16 options from within config.txt - I know that the rotate_lcd=1 option works in FKMS, but I’m throwing it out there that the problem I had might have been the overscan options in conjunction with the FKMS OpenGL driver - I haven’t tested this, but thought I’d comment here for others who might visit this thread in the future.

Thanks everyone - I have a few days off, so have restarted my build - so far so good, but it’s early days.

Have enabled the Full KMS, rather than the fake, and rotated using xrandr - hopefully that will keep it stable.

I really appreciate the feedback.

Hi All,

I’m asking this question here for advice on how to proceed as much as seeking a solution.

I’ve recently installed Magic Mirror on a Pi 3 B+ (brand new, first install on this Pi). I flashed Raspbian using Etcher and installed MM from the auto install. I installed the fkms OpenGL and set the config to rotate_display 3. I installed the MMM-PIR-Sensor module and played around with this, but couldn’t get it working - in the end I removed this from the config, but didn’t remove any components of the module. All else is working okay, except the transitions of the text on the screen is a bit jerky. I checked the temperature of the Pi from a console command and it was 58.

My major issue is though, that I’m occasionally getting what I can only describe as a HDMI crash - I get a scrolling diagonal black and white glitched screen. I think this is on HDMI only, as on the second time it happened I switched the HDMI to a second screen and the error displayed in the same way on a second screen. I was also able to connect via VNC to the pi and the VNC session didn’t display the same problem while the problem was visible on the monitor.

One thing that I will stipulate is that when I started working on the build, I had the pi powered from the USB ports on the monitor - when I started troubleshooting the PIR problem, I noticed the 5V rail was only supplying 4.8v, so I have operated in an under powered state for many steps - I’ve plugged in a pi3 power supply now. (The 2.5amp ones)

So, opinions please - I’m thinking I might just need to start again, forget the MMM-PIR-Sensor module (use some Python for that) and see how I get on.

Is the fkms option a good choice, or should I have gone the other suggested route and used the kms openGL?

Or, has anyone else had this issue with the HDMI and know a fix?

Or, could this be a hardware problem (even one I’ve caused under powering)?

Thanks all - I appreciate it.