A few days ago, a new firmware for the Ditto X2 came out.
The TC electronics website lists the following changes:
Changes in version 1.2.00
additional support for 16 bit audio files (aiff and wav). For better compatibility with existing DAWs you will now find 2 additional 16 bit/ 44.1kHz audio files in the Ditto's track folder when storing your loops.
level management for stored audio files. Exported Files will be normalized when exporting them to your computer to make it easier to edit them further in the DAW of your choice
enhanced protection for buffer underuns. This is a new safety mechanism to deal with "bad blocks" of the flash RAM memory chips.
I had the last problem on the list once (the previous loop was not totally erased but came back distorted), so I'm glad that there's a fix for it.