It is noticeable with my 40OHM Ultrasone's, and more noticeable with 32OHM Bose Tri-ports...
Are you using 44.1KHz (both Control Panel and Xonar Audio Center)?
Play a song in Foobar via the headphone out, then stop the song. Now open up the Xonar Audio Center and toggle the out to Speakers/Headphone/Speakers/Headphone/Speakers/Headphone/ you should notice some white noise... Unless your STX is special, in a good way! :)














