Hi Etienne,
Thank you for reaching out and apologies for us not seeing your post sooner – please always email us directly at support@ntp.dk for faster assistance.
I will be happy to offer some quick help, but I will also direct you to Avid Support, since these issues are under their roof. This especially goes for the S1, which is not inside our knowledge base.
My initial thought is: How are you connected to the MTRX and have you updated your OS ? Are you on a Mac ? Please check that all permissions have been granted in the system software. Particularly if you are using Thunderbolt connections (but I sense this is not the case ?)
Kind Regards,
Jon S
NTP/DAD Evangelist and Santa’s Helper.