Port forwarding conflict when using VOIP and router - Can I make one of them "invisible"?

I have a Linksys SPA-2102 and a Dlink DIR-615 router. The only way I have been able to get web browsing AND phone calls to work is by:





%26lt;Cable/DSL Modem%26gt; --%26gt; %26lt;VoIP Box%26gt; --%26gt; %26lt;Router if needed%26gt; --%26gt; %26lt;PCs%26gt;





The only issue with this is that both the VOIP box and the router are trying to assign IP's to the computers, and so far the router has been overriding everything.





For example, now I can't forward any ports with this configuration. And while there is a port forwarding option in the SPA-2102, the assigned IP addresses differ from the one in the router (192.168.7.# vs. 192.168.0.#) and I have no idea how to change that. I have also tried:





%26lt;Cable/DSL Modem%26gt; --%26gt; %26lt;Router%26gt; --%26gt; %26lt;VoIP ATA%26gt; %26lt; PCs%26gt;





But then I don't get a dial tone and can't receive any calls.





So my question, is there some way to run one of these in stealth or invisible mode so that I can forward ports again? I have searched and read things about DMZ, bridging, and multi-cast threading but i dunno what would work.
Port forwarding conflict when using VOIP and router - Can I make one of them "invisible"?
Keep the


%26lt;Cable/DSL Modem%26gt; --%26gt; %26lt;VoIP Box%26gt; --%26gt; %26lt;Router if needed%26gt; --%26gt; %26lt;PCs%26gt;





Plug your VoIP box cable into the WAN/Internet port on the Router. Now, assign your router a static WAN IP (One that the VoIP box assisgned it). Now, on your VoIP box, foward those same ports your have on your router, to the static IP you assigned your router... You are just double port-mapping.