Reply to Traktor s4 and macbook pro setup issues with headphones - numark phx usb

Hi there everyone

I have just treated myself to the new S4 mk2. I have 2011 Macbook pro.

I simply connected the S4 and it auto mapped itself to the my exsisting Traktor pro software already installed on my mac.

Now my issue is the headphones and speakers. I simply want to run my logitech laptop speakers. NI instructed me to:

Just open Traktor - Preferences -> Audio Setup -> Audio Device and chose "build
in", then the sound will come out of your computer speakers and you can still
control the software with the S4.

So i did that, but I still have no sound coming through the headphones via the jack at the front of the S4 - am I right to expect that the headphones will act as monitor headphones( via the front jack) or do I have to set something else up like my Numark PHX USB headphones, which Is what I used to use before with Traktor and a M-Audio Torq Xponent.

Please help!

Cheers

Shane