Hi carlyle705,
Can you get an official word from
freephoneline.ca as to exactly what ports should be forwarded? I tried searching their website and forum. I found various recommendations but could not find an "official" or "sticky" recommendation from FPL.
You could try enlarging the UDP port range to something like 16384-16998. Also, I saw one post where they recommended the forwarding of UDP 13000, albeit for most softphone configurations.
When you are using the OBi202, is it connected directly to a modem with no firewall, or is it connected to another router, which is then connected to a modem? If you are running a router between the OBI and your internet modem, then setting the OBI in Bridge Mode may be another option.
Lastly, though this may not be the solution you want, the OBi202 does include a DMZ option. You could try placing your Linksys ATA in that DMZ. If your problems vanish, then we know it's most likely a NAT issue that can hopefully be resolved by determining precisely which ports need to be forwarded. Worst case scenario, you could set up your network for a wireshark capture to see exactly what ports would need to be forwarded.
Some ideas,
pc44