Nortel Contivity - Random End User Disconnects

[Elderusr07]

Hey folks,

Looking to see if I can find a bit of assistance on this or if anyone has seen something similar and it only started acting up recently:

Scenario:
End Users are getting reports that they are connected to VPN through Contivity solution (Avaya VPN Client/11XX Series phones in VPN Mode) they randomly disconnect all within moments of each other, while some users stay connected. It resolves itself within a minute, and only seemed to occur after making a change to LDAP Server details trying to move the LDAP Queries from one NPS Server to another NPS Server.

There is only a load of maybe 75 users using it at a time, so its not CPU/ect I wouldn't think.
I've also investigated the amount of inbound/outbound traffic at the time, verifying that it wasn't a DOS or Network spike.

Software Version: V05_00.136
Hardware Version: Contivity 1740

Thoughts? Ideas? I've recently inherited this solution from the previous network administrator and trying to replace all endpoints/clients that connect into it.

Thanks,
ElderUsr