Beyond the good info above, are you trying to use the digital IO and if you are, what devices are you connected(and which connector are you trying to use)? The reason I pose this is because getting the digital IO to function can be quite non-intuitive. It may also help to know which cards are in which slots(because its possible that some slots will only work with certain cards. Traditionally, with the "standard" 192, top left would be analog input, bottom left would be analog output, top right would be digital and bottom right would be EITHER analog input or analog output. And remember that the 192 DIGITAL cannot use analog cards at all. More info may get you better advice
