dual monitor S-video to composite

[Stillwater]

I am attempting to convert the S-video output from my video card to composite video.
Scenario 1: The dual monitor cards works perfectly if I plug the S-video cable directly into a TV. I purchased the Radio Shack 15-1172 4-way distribution amp to convert the video. If I first connect a S-video cable directly to the TV, power on the computer, everything works perfectly. Then if I move the cable from the S-video TV input to the distribution amp. which converts the video signal to a composite output, and run a RCA cable from the Video DA to the TV, the dual monitor video output works with the TV receiving a composite video signal.
Scenario 2: If I would plug the S-video cable into the Radio Shack amplifier, run a composite video cable to the TV and then turn on the computer, the computer doesn't recognize that the cable is connected and the dual monitor output does not work.
Has anybody used this Radio Shack video Amplifier successfully or are the other solutions?