The touch button, the LED and the IR sensor are all in the front of the box and connected with the same cable to the mainboard. Maybe that cable is not fixed or defect. Easiest would be to open the box and check that cable. A picture for reference: DM525 flashen über StandyBy Taste
I dont wanna open the box. Do you think the box is broken? If so, i will be forced to return it.