I’m experiencing an issue keeping a Cisco 7975 VoIP phone for a remote corporate user connected via vpn. Unfortunately I am not an admin for the IP phone, and cannot change/view much of the configuration. The 7975 is initially able to connect via VPN and register. After a (seemingly random) period of time, the VPN connection will disconnect and will attempt to re-establish itself. This disconnection typically occurs several times in an hour. Occasionally the 7975 is able to reconnect on its own, other times it will require the user to manually re-enter their credentials. While the VPN is active, the phone functions as expected.
The above behavior started to occur immediately after switching routers from an Asus consumer model to the Surf SOHO MK III (running firmware 7.1.1). After a few days trying to resolve the issue with the SOHO, it was necessary to fall back to the Asus. Since returning to the Asus, the 7975 VPN connection is solid, with no disconnections noted at all. Any suggestions on how to resolve this would be much appreciated, as I would MUCH prefer to be using the SOHO.
Thanks for reading, and if any additional information would be useful please let me know, and I will provide whatever I can.