XDJ-RX2

I've got a 2nd hand xdj-rx2... When I checked the device all was working fine.... during my first gig, a issue came out. chanel 1 and master out got crazy.. At the minimum gain, the volum signal goes to red.. same for the master out..

I v tried to change and update the software.... it seems to work well after but for my second gig with it.. The same isssue came back and now the cue of the channel 2 of the headphone active the input of the channel 1.. and other button turn on the light??

What should I do? I think I just need to go a shop for a service after sell??