Selca 3045 freezes when the network cable is connected

Hello,

I have 3 CNC´s with selca 3045 controllers and for about a year whenever I have the network cable connected to the machines after a few minutes they freeze. I have to shut down the machines to get back to work.
At this moment, I only connect the cable when I need to call a program and disconnect it immediately. If the cable remains connected, the machine stops.
Does anyone have a suggestion of what is going on?

Hello
I need a backup of the selca s3045p controller , can you give it to me?? Thank you