Resolution: Aram from 3CX contacted me and had a look and said my configuration was essentially correct. He had me install the most recent beta version of 3CX to see if the updated template for my phone would work. This has solved the issue for me. Hello all, Recently I was very pleased to see the licence changes in 3CX and have decided to take advantage of the fact that 3CX can now manage my Grandstream GXP-1610 IP phone. However I have noticed an annoying problem that I have. The latest version available from firmware.grandstream.com is 220.127.116.11, however I notice that 3CX wants to install 18.104.22.168. When I allow 3CX to update the firmware on this phone, the phone enters an endless cycle of rebooting. Once the phone reboots, it does register but then appears to lock up / become very unresponsive to button presses. After a few minutes the phone reboots itself endlessly. During this time I am completely unable to make or receive calls. Downgrading back to 22.214.171.124 seems to fix the problem, but then under "phones" in the 3CX management console It shows up, I can provision it, the request is sent to the phone, it reboots, registers, works proplerly, but shows up red and under firmware it says "not supported" and unless I delete the firmware from the webserver it will try and update the firmware and then we get the endless reboots. I have tried factory resetting, reflashing the firmware, and even using the beta 126.96.36.199 firmware but even this firmware does not work correctly. I have also googles around for things like "Grandstream phone rebooting" and the model number, and variations on this, but I have been unable to find anything helpful. the PBX itself is running on a FreeBSD Bhyve guest running Debian linux, and I manually installed 3CX. I've given the virtual machine a 25GB virtual hard drive and access to 2GB of RAM, there are only 4 extensions. Everything else including the 3 3CX softphone clients is working normally. Does anyone have any ideas on what I can try further to resolve this issue?