I had the same problem, sort of. Every time I got a call on skype everything but my skype call would play through my speakers, while the skype call took over my headphones. For the longest time I just left my speakers disabled, but that meant i couldn't hear sound in certain programs like Second Life.
I set skype to play through "speakers and headphones" and now all my sound goes through my headphones when they're plugged in.
I have found a solution, i had the same problem. If you go to personalize then click on sounds,then click on playback, its at the top. Then just disable speakers. Hope this helpedoh yes almost forgot, remember to set your headphones as default i play alot of games like spore, world of warcraft but the sound still plays through headphones :P
I know that this post is somewhat old, but read my post on a different thread here:
Sound coming from speakers when headphones attached
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