I recently switched from Linux to OS X and last weekend I started having some issues with my Sky Broadband.

Last weekend I noticed that when I started my text editor (emacs 24) and also an IDE I occasionally use, it was taking over 30 seconds to start.

If I disconnected from Wifi, the two programs started immediately.

I then noticed that the router DHCP server was telling OS X to use the router's DNS server and I imagine this is part of the problem. If I use a different DNS server (e.g. Google's), everything starts quickly as expected.

I dug a little deeper and this is the issue. Using Sagemcom F@ST2304 and whatever DNS server it is running:

Code:
$ time python -c 'import socket; socket.getfqdn()'

real	0m30.082s
user	0m0.012s
sys	0m0.005s
Using Google DNS:

Code:
$ time python -c 'import socket; socket.getfqdn()'

real	0m0.326s
user	0m0.012s
sys	0m0.006s
Any hints as to what's going on?

Thanks.