these outputs are going to be the red/white RCA cables, usually labelled "audio out." They should be located in close proximity to the video out connections to the TV (unless you're usuing component video - in which case, they sometimes separate these connections).
Check out the back of your receiver. If you're going from cable box to "TV video in" and "TV audio in" and then from the receiver to the TV going from the "TV video out," then the audio from the receiver to the TV should come from the "TV audio out" (two RCA - red/white) to the "audio in" portion on the back of your TV (the same input of course that the video is being input on the TV). This will get you sound and video from the source to the TV.
