Ok so I just wanted to test my 3g modem on my 2820.
plugged it in and it was supported picked up an ip and both WAN1 and WAN2 seemed ok. Could not surf everything seemed slow so unplugged it.

Ever since I added the 3g modem the seconday dns shown on the online status is wrong. It seems to come from the 3g modem's isp and not wan1 isp. Even after unplugging and rebooting has not reset.

how can I change it back? ideally should be from dhcp for wan1.