2. What should I do if the K7 BT is abnormal?

[No sound, noise, unable to boot, indicator light off, etc.]

You can try the following methods to help you solve the problem:

1. Restart K7 BT

2. Re-plug the power cord

When the two indicator lights of COAX and OPT are on, it may be that the output port has short-circuit protection:

Please replace other output ports to check

Do not use the 4.4 to 3.5 adapter cable to connect to K7 BT

K7 BT has overload, over-temperature, and over-current protection mechanisms, and whoever triggers it first will be protected first.

After the protection is triggered, you must turn off the power to restore it. You can turn it off and then on through the knob, or directly unplug the power supply to restore

The DC protection is to prevent the machine from damaging the earphones. If it keeps triggering and then triggers again soon after recovery, it means that the machine has a rare problem and needs to be returned to the factory for repair. Please contact the seller or support@fiio.com about that.