I have two KH310, one of which has normal sound and function, but the panel light is always red. After using another circuit board for troubleshooting, I came to the conclusion that its main board (the back of the speaker) is faulty. After troubleshooting, it was found that the LED lights are controlled by the comparator lm339/393. I replaced them, but the problem still persists because its circuit board is multi-layered and I cannot see the wiring inside. Therefore, I am seeking help, Has anyone encountered this situation before?
The following are photos of the circuit board. I hope someone can help. Thank you
The following are photos of the circuit board. I hope someone can help. Thank you