Hi, I have just purchased a FOC830 Optical - Coaxial signal converter unit, because my speakers are coaxial digital in and my laptop is optical audio out. I know that this is the right piece of gear, but I'm not sure what type of optical lead fits into it. I know nothing about optical leads, but the computer needs one of those long thin optical jacks on the end of the cable to fit into the soundcard. The other end of the cable has to fit into the FOC830's square 'optical in' socket. I am currently using a standard short plastic optical wire made by sharp, which I used to use for minidisc recording. It has the correct end for the soundcard ie. a round long jack with a metal tapered end, but the end that plugs into this converter device, which is square and has two flattened corners on one side and convex lines running either side of the square (ie. Toslink), doesn't seem to be right, even though it partially fits into the FOC830. I am getting a sound signal, but only when I plug the square end into the converter so that it is barely a couple of mm into the socket and fairly loose, and when I push it in all the way, as it needs to be for secure connection that doesn't come undone, the sound signal goes completely and I get static. Therefore either the converter has a faulty socket, or the square end of my minidisc cable is not right for the converter (unlikely as I thought toslink was a standard shape of only 2 possibilities), or my cable is faulty. Could anyone suggest anything on the correction of cable front? I will try another cable in the meanwhile to check that mine isn't faulty. Many Thanks Harry Shearer.