Thank you for your replies. I have updated the title as it was now misleading as to the primary problem.
Earlier builds were not Manjaro. That is a more recent change.
SD card is fine, EMMC appears fine. Behaviour is the same irrespective of boot source.
I believe this is a hardware issue.
The machine will boot and run for a short while (from seconds to a few minutes). The display will then show various corrupt / garbage lines, and the machine will stop responding.
Possibly thermal-related; if it warms up the non-power on behaviour temporarily returns.
As the plastics are also breaking already despite minimal use, and as I’ve not got spare time for debugging the hardware, this will sadly be consigned to e-waste. Hopefully the other parts can be used for something else.
Earlier builds were not Manjaro. That is a more recent change.
SD card is fine, EMMC appears fine. Behaviour is the same irrespective of boot source.
I believe this is a hardware issue.
The machine will boot and run for a short while (from seconds to a few minutes). The display will then show various corrupt / garbage lines, and the machine will stop responding.
Possibly thermal-related; if it warms up the non-power on behaviour temporarily returns.
As the plastics are also breaking already despite minimal use, and as I’ve not got spare time for debugging the hardware, this will sadly be consigned to e-waste. Hopefully the other parts can be used for something else.