Alienware aurora R4 audio problems

Hello, starting to pull my hair out now as I cannot find a answer for my problem.

Just bought a alienware aurora r4 the base model with the chassis upgrade and wireless upgrade, graphics card is amd r9 270, im using a samsung 24 inch hd moniter (s24c570L) it has speakers built in, ive plugged in my headphones and theres sound coming from it.

im using a hdmi cable and had no luck with the sound coming from that so i bought a audio 3.5mm cable and still no sound, i set the moniter as default in sounds etc and even disabled the speakers and realtek audio output and then tried it but again nothing.

I plugged the audio 3.5mm jack cable into the back of the computer into the green port as speakers out, I have tried all apart from the mic and tried a restart after every attempt, is that the right place for it? im getting some logitech speakers tomorrow and was going to use a splitter so the moniter and speakers would work at the same time but not sure if that will work?

any advice would be great and much appreciated.