Do these USB sound card modules replace the stock internal when used for recording ...or?

hers my dilemma.....my Realtek SC internal plays back fine ....but when I try to record something using the front or back Inputs using Acid pro....or Adobe Audition etc ....I only get a one sided track recording NO STEREO....there is no signal on the right side......when I tried to use the balance on the mixer its dead on one side.....Im thinking my sound card is defective for recording...playback is fine ?

[This message has been edited by Dnj (edited 05-03-2007).]