Stage rack 2 lost

[bop]

Hey there,

little question......
Setup is as following:
Venue D-show with sidecar 64 inputs on stage.

Lately it occurs more often that stage rack two is not recognised on startup.
We've got this board inhouse so it doesn't move that much, stage racks are in solid place and don't move at all.Boards are taken out 3 times a week when bands bring in their own boards.

The solution to get our stage rack 2 back is hard resetting the stage rack, by switching the green buttons on the back on and off. It immediately recognises the stage rack again, but still, i don't want this to happen.
What can be wrong? We tried to use different coaxial lines, same issue.
Is it maybe something in the link cable from board to computer?

Anyways,if somebody out there had the same problem, let me know, hope you found a solution for it as well.