The documentation says that this product works only with iTunes and hasn't been tested on external drives. I have a fairly noisy external drive and I opened a CD using QuickTime Player, and was pleased to hear that Scharping worked with both that CD player and with QuickTime Player. It also works with Flock (the browser) so I imagine it works with others.

It certainly keeps the drive quiet - it's like playing a CD using the internal drive, only much quieter. I could barely hear the drive at all.