Sounds like we have the same problem. I just noticed there are several threads on here with no response from line 6

This is a bug in Line 6 Monkey 1.50. We suggest downloading and using Monkey 1.43 to update your Flash Memory, it can be downloaded from the link below:

Monkey 1.43 Windows:

http://line6.com/getrelease?rid=4223

Monkey 1.43 Mac:

http://line6.com/getrelease?rid=4222

When the update asks if you would like to save presets, select 'NO' and continue with the update.  This should resolve the issue. The other option is you can download and use Monkey 1.43 and use it to update your Flash Memory:

The other option is to stay with Monkey 1.50 and when the update asks if you would like to save presets, select 'NO' and continue with the update. Make sure to back up your custom presets before updating your POD's firmware using the instructions at the link below:

http://line6.com/support/docs/DOC-2613

Once the firmware has been successfully updated to v1.40, you will need to perform a Global Settings reset and a pedal calibration using the instructions at the link below:

http://line6.com/support/docs/DOC-2222