Mr. This device is for europe use only if you are over there , the device have a qos setting speacily for the Voip service , however if is not responding is because the voip signal travels on the firewall and im preety sure you will need to open those ports on the router , go ahead and call the voip service company so they can tell you what ports you need to open on the router . i hope this infomation is usefull for you and the product works .
