Unresponsive GUI or SSH

[dwebster]

We purchased 5 brand new ws-250-DC's out of the 3 we have used, we are getting an unresponsive GUI or ssh access every few days. We have 30+ major distribution sites and only the last three on 1.5.5 are having these issues.

There are five ports being used, 3 48v HV for Mimos A5c's and one for fiber and one copper as a backup to the fiber that is disabled unless needed.
The odd thing is that I've noticed it only happens when the Mimosa's are connected at gigabit, there are no errors on the port but if I set them to 100mf-auto it seems fine and the switch then become responsive, i know when it's happening because typically one of the A5C's will go offline but the port shows up when i can get in. It isn't the fiber because i've tried the copper port as well and it was tested on the tower prior to being hooked up and the netonix typically pings all while this is going on. We are using a Tycon Power systems controller for DC power and they are hooked up to the load side at 48volts. Has anyone seen this happening with these switches?

Should i down grade the software?