While technically there is no "Clean Preset" on the Fender® G-DEC® 3, many of users have found that using the Jazz Master amp model setting with the Compressor off and the Timbre set to none will produce a non-effected, neutral sound. Also make sure that the treble, mid, and bass controls are all neutral.
For the Fender® Mustang Series products and the Passport® mini, the '57 Twin Reverb amp model with no Gain or effects is a good place to start for a "Clean" tone. Then you can launch AmpliTube and use your Mustang Series product with this software. For Mustang (V2) Series amps and the Mustang Floor, users can select the Studio Preamp amp model which is intended to be a clean model.
With all previous AmpliTube versions (Including AmpliTube Fender LE/SE ), you are required to download AmpliTube 3. This is due to AmpliTube 3 being updated and supported with new features, 64-bit support, AAX support, and much more. You can register using their AmpliTube Fender LE/SE serial and that gear will then open up inside of AmpliTube 3 for continued use.
Complete the process as normal. The Fender LE/SE gear should then be appearing for you. If for any reason they are not seeing the Fender gear, please follow the quick steps here: