Disable fetching DNS servers

In my network I have 2 adsl lines being loadbalanced by MK, each line is from a separate ISP with different DNS servers so I’ve elected to use OpenDNS, however whenever one of the lines reconnects it overwrites the DNS servers with its own (PPPoE interface). Is there anyway to disable that ? I’d like the DNS servers that I set to be permanent.

If you open PPP > PPPoE_InterfaceName > Dial Out you will find a checkbox for “Use Peer DNS”. Uncheck.