Zynthian 5.1 RPi5 issue after assembling

Hello-
I had this same issue. This fixed it for me: Zynthian 5.1 RPi5 issue after first boot, red LED on + green LED blinks 3 times - #4 by jofemodo

If the issue persists, please try disabling the overclocking in the SD-image before booting the zynthian V5.1 for first time. It must be a fresh burned SD-image. I mean, you never tried to boot with it before. For doing so, follow this instructions:

  • Burn a fresh SD-image with the latest stable
  • Mount the SD-card in your computer
  • Edit this file in the root partition (the bigger partition in the SD-card):

/zynthian/zynthian-sys/config/zynthian_envars_V5_pi5.sh

  • Replace the overclocking value from “Medium” to “None”:

export ZYNTHIAN_OVERCLOCKING=“None”

Umount the SD-card and try booting your V5.1 with it.

It seems that the number of RBPi5 boards not supporting overclocking is higher than expected and we should disable overclocking by default. Currently it’s set to “medium”.

I also had to power cycle the Zynthian. It didn’t work the first time I turned it on but then it did when I turned it off and back on again.
Joe