You know, I had the same problem. What's your setup? I have Cakewalk PA9 and everything works fine, except for a latency issue that I'm trying to resolve. OK, back to your problem....What exactly do you have connected to the US-122? In order to get sound, you must configure your PC/laptop to use the US-122 as it's playback and recording source. ((Control Panel ---> Sounds & Multimedia ---> Audio tab). Then, you have to set your Cubasis software to use the US-122 as it's source to receive and playback instead of your sound card. That's the first step. Then, make sure the your guitar is in one of the guitar inputs and not a line input on the US-122. Plug in your headphones, and turn on Direct Monitoring. You shouldn't have any problem hearing anything from your PC or your guitar. If you have any more problems, just let me know.