FA-101: Pops and Clicks using the FA-101 with Fujitsu Notebooks
Fujitsu notebooks have a program that runs in the background called "BtnHnd.exe". This program constantly queries the CPU and can cause problems in your audio stream. Find it and disable by hitting CTRL-ALT-DELETE then clicking on Task Manager, then Processes. Find BtnHnd.exe and right click on it, then select Disable.