I recently installed a Sophos UTM Home firewall at my home. It seems very full featured and powerful. However, my ooma device stopped working when I set it up. During setup of the Sophos box I told it to allow Voip communications as can be seen from the screen capture. Here is what my network looks like:
10.0.0.0/24 network --> Cisco Router --> Sophos --> ISP
My internal network is a 10.0.0.0/24 network. The Sophos box is address 10.1.1.1 and the Cisco router has a static IP of 10.1.1.2. Sophos is configured to consider any "10" address to be internal (i.e. 10.0.0.0/8). Web browsing works fine, so I know I'm connected to Internet. However, for some reason it is blocking my Ooma device.
Have you explicitely allowed the ports used by Ooma, as these are not on the standard "VOIP" ports?
It looks like you haven't.