Got 3 stores, each location has a UCM6204 all tied together through site to site VPN. Every phone is a GXP2170. Using Eventlist BLF so each site can see each other extension, transfer calls etc… All working fine. Setup remote extension to “Site A” and registers fine, 2 way audio working, can call the remote extension without issues. When I dial out to test calls, it will just sit there for a bit, the extension will go gray and back to green, my Pageall speed dial BLF will go gray, and all the eventlist BLF lights from site B and C will drop. Tested with a GRP2614 and does the same thing. Sometimes, I would say 1 out of 10 attemps, I can call out with out delay and Eventlist BLF lights work fine. Have tested phone from various locations trying to see if it was something with the ISP but acts the same no matter where I am.
I have remote phones at other sites without issues, but this is the only place that has 3 UCM tied together. I have also tried using older firmware and the lastest beta firmware. Anybody else ever had this happen?