Polycom IP6000 and Allworx 24x. The IP6000 is registered and works fine on calls to other Allworx stations in the building. We have no incoming audio on off-premise calls (which are all VoIP through the corporate WAN and hit the PSTN in another city). The corporate IT people think it's a VLAN issue...they apparently have talked to our vendor and haven't figured it out yet. On the IP6000, the VLAN settings appear correct. What are we missing?