Can we undo firmware update?

Yes, the URLs to the less recent versions work; but I was hoping to roll back to an earlier version (01.01.11), to ensure I’d be free of the Slot Radio adware. But that link “post” is invalid:

http://forums.sandisk.com/t5/Sansa-Fuze/Roll-back-firmware-update/m-p/72229/highlight/true#M5440

Oh well, I’ll try v1.02.26 from Black-Rectangle. If I still get the pesky adware, I’ll learn to live with it. Thanks for your patience.