XPS M1710 and 5.1 speakers... Suggestions?

Ok, so i have a Top of the line Xps M1710 but for some reason they like to not let us use 5.1 or 7.1 speakers. I have a set of 5.1 speakers right now, and what i Could do is just get a mini-jack to red white converter cable and then i could plug that into my little 5.1 converter that came with my speakers, and at least that way i would be able to get all my speakers sound.(right now i have the green mini jack plugged into my headphones and am only getting my front right and left speakers to produce sound). Any so what do you guys think about that idea. Got any better ones? External sound card possibly? Any ideas would be helpful thanks!

Edit: Just one other thing ive noticed, is that every now and then(like every 15-30 seconds) there is like a little blip in the music, kind of like the music stops for a split second, any of you know what might be causing that? Or even what to call that kind of thing(i dont know). Thanks.

 

Does the "blip" sound like a skip, or a beep? It's kinda hard for me to know exactly what you are talking about.. Maybe I can help after I figure out.

 

hmm, its like a skip, it doesnt really have a tone. The best way i could explain it would be if perfect music playback is a straight line, then each one of these "blips" would be a jagged spot in the line.

 

I dont know how much that helps you, but this is getting really annoying, i could honestly care less about being able to use 5.1 speakers if the sound sucks, I would like to at least get good sound through my headphones..