On your desktop there should be a little speaker icon down on the bottom-right hand side of your screen. (If it's not there, go to Start > Settings > Control Panel. Once the Control Panel has opened, find the Icon for Multimedia and double click on it. Select the Audio Tab at the top. There should be a check box on that page for "show volume control on the taskbar". Make sure the box is checked.) Double click on the speaker icon and that will bring up a volume control window. Make sure that the "mute" check box for whatever you are using for you sound source (line in or mic) is NOT checked. In other words, you don't want it muted.
You can also, while you are there, go to the pull down menu labeled Options. Choose "properties" and click on the radio button for "recording". This will give a recording window. By raising the level for "line in" or "microcphone" (whichever you are using) you can increase the volume level that you are recording at. There should be a way in your Cakewalk program to see the recording level. Make it as loud as you can without going into the "red". That should do it for you.