> DDJ400 (REKORDBOX) CUE phones plays to Master output too

I am experiencing a very odd issue.

When i hit the phone cue, the audio plays through the device plugged to master out and the device plugged to headphones out.

The audio should only go through the device plugged to headphones output. Does anyone know why is this happening?

MASTER CUE is unlight.

Only the PHONE CUE is light (for both channel).

Everything used to work nomrally, and suddenly this happened ( I haven't found answer to this problem in other threads ) .