Found this on OBS site ?
"This tool was developed for a rather specific purpose: Due to a driver issue, the Dazzle loses its crossbar association after device initialization, making it impossible to open the crossbar in for instance OBS or VirtualDub. This little application lets you access the crossbars for all capture devices on your computer (provided that they actually have one) from a simple window interface.

I doubt this will see much use except to get sound directly out of Dazzle devices, but it can be used to switch inputs on things like Avermedia cards if you don't feel like opening the properties for the source in OBS."

I know what crossbar is, So what happens when you switch to S-Video using crossbar thingy?

I don't know what crosbar is apart from what I've read on this forum and via Google. Is it a part of VLC Capture or Vdub ? The results (or lack of) are the same whether I connect the camera to the grabber via S-Video and component audio (Red/White) or all three component leads (Red/White/Yellow). I've hopefully attached a pic of the grabber.