Driver losing connection to Configuration Server

[PFCCWA]

Hello,

Is anyone familiar with third party ivr (xml) drivers and experienced failures/connection losses?
we have come across scenario where driver is losing connection with config server, then reconnecting, but sometimes fails.
Config server logs show:

[b][i]Trc 24301 Extended info : Client [18] disconnected, application [IVRDriver], type [IVRDriver], protocol [CFGLIB][/i][/b]

Driver logs:
[b][i]Std 04502 Cannot connect to Configuration Server 'confserv' at host 'host', port 2020, reason 'unavailable'
FL|ffffffff|IVR_Driver::: The Configuration Server is unavailable, attempting to restore communications[/i][/b]

What can I check to determine root cause?  sounds like network disruption between both hosts? no other host or app affected at same time.
One solution suggests reason is app requests all DNs from config server in large environment but cannot see request in logs around this time and it is rare occurrence.
Solution is MPS IVR.

thanks,