We currently provision our h.323 phones with vpn firmware. While these do work for the most part they are difficult to manage. We suddenly have issues with multiple remote users having no audio once connected and some that sit and discover. The vpn tunnel establishes with no problem and there are no firewalls once inside. In running a packet capture we see the call server rejecting registration with an unknown error. In searching various threads all it says is to contact your Avaya administrator. Has anyone seen this before? This is coming from the PE of the duplex call servers.