Alienware X51 R2 Sound Issue

Alright, so, about a week ago, I was on Skype with a few friends. And I was toying with audio (effects and things like that), and I wanted to see what different sound channels I could use with my particular headset because it was new. So, I changed the setting to something one setting higher and my audio completely quit working. No matter what I use, headphones, speakers, or if I connect it to a television via HDMI cable. I need to know if there is a fix or not, because I really don't want to go through the trouble to send it back. Thanks.