Cdj 2000 nexus digital out issue

Hello , this afternoon I turned on the CDJ and I noticedthat one of them did not send signal. Both are connected to a djm 900nxs digitally . I can not understand what happened . This morning I turned on the CDJ to try some tracks and it was all ok . I tried replacing the same cable , connected to the same input of the mixer to both outputs of the CDJ . One sends the signal , the other not. So is ruled out a problem with the cable or to the mixer . Has anyone ever had a similar problem ? Possible solutions? Thank you