Mooer Leveline volume pedal dissected. How on earth does this work???

[slacker]

Looks like it to me, if you can run the pedal when it's not in the case you cold test it by waving something shiny back and forth in front of it.

[duck_arse]

the linked-to datasheet says 940nm peak emission for the led. infra-red, says a popular search engine.

play nasty - shine a teevee remote control at the sensor.

[potul]

Yep, it looks like a reflective sensor, similar to the ones used in "line following" robots.

try simply to wave sometihing in front of it....