I have this kind of bothersome error that pain me. I've an ADSL line with Libero/Infostrada ISP normally stable.
My router is a Netgear dg834 (firmware 3.01.29).
When I connect my PAP2-NA firmware 3.1.22(LS) to the router the Internet line drop down after few seconds, with "Loss of synchronization" router log error.
During the short time of line up I was able to call and receive calls through my voip provider (messagenet.it).
The Pap2 receive the lan config from the DHCP and is always configurable from his web interface.
I've tried to disable the two voip lines, but nothing changed.
Any idea. Thank you.
I have this problem too.