1. Why is there no sound out?
1) Please check if the product is powered.
2) When power is supplied to the product and the input signal is inserted, make sure that the fiber optic connector has light.
3) Please check if the audio format of the input device has been set to PCM/LPCM.
2. Why the noise?
1) Check that the AUX/RL input connector is fully inserted into the interface and try rotating the input cable. (Please use a good quality AUX/RL cable)
2) Please check if the audio format of the input device has been set to PCM/LPCM.
3) Check for interference around the input/output cables.