Intermittent Boot Issues

[khanku]

I haven't had the opportunity to install the new U-boot, since (as I understand) I'll need an external keyboard for that and I haven't one on-hand at the moment. However, I have found that the device usually boots up just fine if I hold the power button for longer, usually  a second or three after the power indicator actually lights up.

I think you might be confusing keyboard/track firmware and u-boot. There is no need for an external keyboard to dd a different u-boot to a SD or eMMC.


Having now gotten a serial cable I can now see how Manjaro's u-boot often leads to the initramfs failing to find the root device and thus getting stuck. While no obvious error is shown the manjaro build does not show debug messages like mrfixit2001's does so I can only guess some race condition leads to the eMMC not being available when the kernel boots.