Below is basically the same message I posted on several forums.

I have an unlocked DVG-1402S that I purchased which came with nothing programmed into it. I used to use it with my first VOIP provider, iTalk here in NZ. It worked reasonably well except that every few days it would disconnect and I would have to go into the web interface and tell it to re register. As the registration timeout was set for 1 hour it was not failing to re register every single time but about once every week or two weeks it would somehow lose connection to the server because the Query button would produce some sort of error or other message indicating it was not registered.

Anyway I decided to switch providers to 2talk here in NZ and this has brought more problems because now I cannot make any outgoing calls on it but it receives incoming calls fine. Both of DLink Support and 2talk say there is a compatibility problem, the most obvious sign of this is that the outgoing proxy server cannot be set by FQDN, only by IP address.

I have heard that the DVG-1402S is a bit of a lemon, it is not very common in NZ, there is no newer firmware available that I can see and the providers here seem to know very little about it.

Part of the reason I bought it is that I changed from a DSL provider to a cable provider and the modem changed from one with full router capabilities to a basic cable modem with limited capabilities. My old DSL modem had a DHCP server and router in it and with a network switch connected to its output port it would generate IP addresses for connected computers and route them through to the Internet. The cable modem doesn't do any of this stuff so I was compelled to buy a new router to plug into it to add the same capabilities that I had originally. I switched to VOIP at around the same time and looked for a VOIP capable router that could connect my old cordless phone as well as the other capabilities mentioned and this D-Link was a good price and it does all that stuff as well.

Firstly, what do other manufacturers produce that is equivalent. For example Linksys (1 or 2 analog phone connections, WAN and Ethernet connections, DHCP server and router)

Second: Here are the instructions for setting it up that my current provider have put out:

Third: Here is the response from DLink Support to the query I raised about the connection problems:
"You may find that the DVG-1402S is not 100% compatible with your new VoIP Provider as per why you are unable to complete a SIP Call.

Could you please provide reference to broken tone, do you refer to engaged signal? What is the Router in front of the DVG-1402S, does it have SIP ALG enabled and have you tried to disable it and setup SIP Port Forwarding to the WAN IP Address on the DVG-1402S? Whom is the new provider you are using and have they tested the DVG-1402S with their infrastructure? What are the setting which you are using with your new provider?"