I have not been able to get my new ooma telo VOIP device to work. The ooma technical support had me connect my computer to the LAN side of the ooma device to access a web interface inside it, and using the interface I scanned the ports of the ooma device and found that most of them were found to be “allowed” but two of them were “denied,” namely UDP ports 53 and 123. The support person said that either my router, a Surf SOHO, was blocking the ports or the ooma device was defective. In the router there are no firewall rules established other than the default. SIP service passthrough is in standard mode, and I tried defining two custom signal ports as 53 and 123, but that did not help.
I suggest you to use wireshark that help you to find where is the problem .