Sound Card/Sound Problem

ok heres my problem, i have working sound on my comp. what im trying to do though is record a game i have on my comp. through another program, the problem is after i record it an play it back theres no sound from the game on it, i dont think its the game or recording program cause when i edited it using windows movie maker an put a background song it played the song.....but anyway someone told me it might be a soundcard problem/lack of update....im not sure which one is my soundcard but when i go to audio under device manager i have these

1-audio codecs
2-legacy audio drivers
3-legacy video capture devices
4-media control devices
5-sigmatel high def. audio CODEC
6-video codecs

my comp. is a dell dimension c521 amd x2, ive dwnloaded an installed all the drivers for my comp. off the dell site, could anyone help me with this problem?

As far as I know, the only time a sound card is used during a recording is when a microphone is plugged into it. Other than that, it's only used for amplification of sound that is passing through it.

Could there be a protection scheme on the game? What program are you using to record?

i used the program snag it, this comp. i got is a few months old tho, when i did this on my old comp it worked,the game is called mugen, i dont have a microphone, but i also noticed i dont have the options ''mono mix & stereo'' in my volume control like most ppl do..

Are you saying that maybe it's only recording one channel since there is no mix? That's possible.

im saying that, it records the video fine, and when i add a song to the clip it works too, and i have no problem playing songs an videos on my comp, the problem is i dont know why it wont pick up the sounds from in the game when im recording, i have all the preferences checked off, im wondering if maybe its my sound because another program ''hypercam2'' ive tried doesnt pick the sound up either..

Some years ago, I had a VCR with a similar problem. If I recorded over a tape, the video would be replaced with the new video but the sound from the old video would remain. No one could figure out the cause.
I'm lost on that one.