DNS Issues - Cannot get DNS Connection

I recently changed ISP's. Now I'm experiencing issues with DNS resolution.

Off and on I loose DNS resolution connectivity on my new internet connection. I need to get this resolved ASAP. On the untangle appliance I have both set the DNS servers manually and let them be completed via DHCP.

Once I enable the interface I loose all capability to resolve the DNS address. Interestingly for most of the last month this wasn't an issue.

From my broadband gateway, I can connect and resolve DNS entries for this ISP. As soon as I enable the NIC on my untangle gateway and attempt DNS resolution there, I fail. My other ISP's DNS resolution is working fine. I've tried the combination with both enabled, just one, etc but the problem persists. I've even tried different network cards to see if that would address the issue.

For kicks and giggles I also tried setting the new ISP connection as "Non WAN" but enabled. Assigning the IP address manually etc I still experience the DNS timeout issues once this interface is enabled.

How should I go about debugging this?

Running the latest version of 10 btw.