I had an issue where lots of presets were displaying twice or sometimes even 3 or 4 times. e.g If I searched presets for "Bluesy" I had Bluesy night show up twice. This happened for a lot of presets. Clicking on the top one did nothing. Only the bottom one was 'real'. The others were like ghost listings.
Heres' how to fix this.
1 - Backup your custom presets, just in case.
2 - Close Amplitube 5
3 - Go to the directory ...\IK Multimedia\AmpliTube 5
4 - Locate the Presets.db file
5 - If you don't have file extensions showing then go to the View/show menu (windows) and select to have file extensions visible.
6 - Edit the file so it has a dummy file extension. I just added on ".old" to the end
7 - Open Amplitube. This will automatically create a new but empty presets database file.
6 - Refresh presets and the new presest file will populate without all the duplicates.