Headphones not working on Alienware 17R2

I have an alienware 17 r2 with Ubuntu 15.04 installed. I have most драйверы working however I can't seem to get an аудио from headphones when I plug them in. The sound always seems to play only with the laptop speakers whether the headphones пахал plugged in or not. I don't see any notification or pop-up either if the headphones пахал plugged in or not.

In the sound settings, under output I only see Digital Output (S/PDIF) and Speakers but never headphones whether plugged in or not. Even in the alsamixer интерфейс, I don't see headphones volume option.

Does anyone face в сходный issue эксперт this or идея - any how to get this working? Im struggling with this for several weeks now to не avail. Please let я know what additional info I май provide to help solve this issue. Thanks in advance!