UniqueName4Me,
After falling in love with the Norstar, I recently wandered into the BCM world. I too am using a BCM50 R6, and I am also using Voip.MS. While I have learned that there are some things about the BCM that aren't incredibly intuitive, registration
should be simple. I came from the Asterisk world and was using the IAX protocol to trunk with VoipMS, I can't recall ever losing connection in all those years. Traversing a Firewall/NAT with SIP is totally new to me, and boy did I scratch my head for DAYS trying to figure out why VoipMS wasn't working properly.
My issue wasn't exactly the same as yours, rather, I could make outgoing calls with voice both ways just fine, but Incoming calls just didn't work no matter what. BCM Monitor would show for a brief second that there was an incoming call, but it never seemed to make it all the way through to the BCM. In addition, I was getting Alarm 51104 very frequently, and then it would recover with Alarm 51105. I stumbled upon most of the solution by complete accident, and I believe that VoipMS is to blame here.
Go to Voip.MS and login to your account, if you're registering with a sub account from the main account, that's the one we want to tweak. Get to the "Edit Account" screen, and in that page you will see two options under "Device Type"
A: Asterisk, IP PBX, Gateway or VoIP Switch
B: ATA Device, IP Phone or Softphone
When I set up my Sub-Account, I selected Option A, because, well, A BCM is an IP PBX. Wrong option apparently.
Something about the way that VoipMS has set their system configured does not play nicely with my BCM in that mode. Selecting option B solved almost all of my problems immediately. I still am getting alarm 51104/51105 every single day, almost always at exactly 1AM on the tampa.voip.ms server, but the BCM always recovers almost immediately. I have yet to figure out why this is happening unfortunately, but hopefully this information will help you iron out some of the kinks.
Best,
B.