Problem solved! I dont really know what i did,but it worked
Right now i tried to explain it but i dont have a clue how to translate all these weird word into english XD
well,ill try it simplyfied...i opened up the option for sounddevices(rightclick on that sound symbol on the bottom right corner of the windows taskbar...then choose...something that shows your sounddevices,for me it was just "sounds") then there should be...ahh ok ill add a picture even thought its german-.-

soo...ok i rightclicked the symbol in the red circle,then the shown window popped up,at first it only showed me the activated microphone and something other...then i rightclicked that window on empty space and the little window popped up,there i activated the upper option which i think is called "show deactivated devices",then i activated "stereomix" and whoops my fraps recorded sound

Right now i tried to explain it but i dont have a clue how to translate all these weird word into english XD
well,ill try it simplyfied...i opened up the option for sounddevices(rightclick on that sound symbol on the bottom right corner of the windows taskbar...then choose...something that shows your sounddevices,for me it was just "sounds") then there should be...ahh ok ill add a picture even thought its german-.-
soo...ok i rightclicked the symbol in the red circle,then the shown window popped up,at first it only showed me the activated microphone and something other...then i rightclicked that window on empty space and the little window popped up,there i activated the upper option which i think is called "show deactivated devices",then i activated "stereomix" and whoops my fraps recorded sound
