Edge-V resets without prompting

I have the Edge-V inside a case and I boot it from an SD card by clicking the function key three times. The times I was booting it without a case, it was fine. I booted it with the case oncd or twice and it was fine, too. Now, only a few minutes after booting from the SD, the board either resets—in turn, booting from eMMC by way of the bootloader in SPI flash—or the only symptom is the graphical output goes black (this might be a reset that I haven’t given enough time to complete). In both cases, the LED goes from white to red.

What is happening?

Is the power connected to the USB-C on the back of the Edge-V.

looks like problem with power supply : Edge OOWOW bootup fail [Khadas Docs]

So, not the board, then?