Lock button fails at low framerates

This is a weird one—and not the end of the world. Might be some inevitable low-level OS thing. But FWIW:

On hardware, the Lock button has a high rate of being ignored when the refresh rate is set low (like 1 or lower). It can take multiple presses to make the device lock. I thought I bricked my Playdate! But keep trying and it does lock.

Demonstration:

import "CoreLibs/graphics"

playdate.display.setRefreshRate(1)

playdate.graphics.setColor(playdate.graphics.kColorXOR)

function playdate.update()
	playdate.graphics.fillEllipseInRect(0,0, 400,240)
end

PDX attached:
locktest.pdx.zip (8.2 KB)

The following work with no problem though:

• Timed auto-lock seems fine.

• Simulator seems fine—problem is only on PD hardware.

• UNlocking is fine.

(Also: just for kicks I tried assigning .deviceWillLock and .deviceDidUnlock to see what would happen. That didn't affect this issue.)