Nope. This is a local LAN setup at our office. The i63 along with all our other deskphones, PBX, etc are all on the same switch and same router.
We have no problem making video calls from phone to phone or phone to Sangoma Talk, or other brand doorphones (Grandstream GDS3710) to Sangoma Talk or video desk phones on the same PBX, same network…
Its only this Fanvil i63. Unfortunately their support is lacking, I believe their support is in Asia so they are very slow to respond and send screenshots of their setup docs on how to connect to a PBX which is basic stuff we already have done…