I was experiencing these issues with a known-good PSU. The same one has been working fine since I switched SD cards. Undervoltage is a common issue but easy to

I was experiencing these issues with a known-good PSU. The same one has been working fine since I switched SD cards. Undervoltage is a common issue but easy to identify since it shows up in logs and displays the lightning bolt icon in the top-right corner of a display is connected.