Having updated the router to the latest firmware (5.01.17) the problem appears to be resolved (even though the release notes made no mention of DNS. Marking this bug as invalid.
** Changed in: systemd (Ubuntu) Status: New => Invalid -- You received this bug notification because you are a member of Ubuntu Desktop Bugs, which is subscribed to systemd in Ubuntu. https://bugs.launchpad.net/bugs/1609546 Title: Slow DNS lookup through Netgear DG834G V4 router To manage notifications about this bug go to: https://bugs.launchpad.net/ubuntu/+source/systemd/+bug/1609546/+subscriptions -- desktop-bugs mailing list desktop-bugs@lists.ubuntu.com https://lists.ubuntu.com/mailman/listinfo/desktop-bugs