I have been using 3CX for a few months and have great success, however we struggle with communication to our other site. The current config that we use is: Local LAN in our main site (A), all phones talk without issue. Site (B) has a VPN to our internal LAN at (A). The extensions are simply routed to (B) like they are part of the LAN. The issue we have is the call quality is choppy at times and constantly looses voice. If (B) calls (A), it won't connect on first go, but will on the second time. If (A) calls (B) it will connect everytime, but sound quality is low and drops out at random times. What we are trying to acheive is simply communication between our employees, nothing more. I do not need to talk to external lines, etc, just office communication. We have decent DSL in both locations. Any tips would be greatly appreciated.