I have 2 station OfficeServ 500 connected by PRI cards (3m cable)
Everythin works good but several times in day it stop working. I call this station as station A fnd station B.
So it works e.g. 2 hours and after it i can't call from the station B to station A, but i can call from station A to station B. After rebooting PRI cards everythin again works good.

But this trouble can happen in 5 minutes or in an hour or 2, 3, 4, but it happens every day.

Yesterday i have changed cable and PRI cards, but my broblem still exist.

What can i do in this case?