hello, just to inform you that i had several bug while i had a USB external storage connected to the KPA :
i had a DSP error message while playing,just after browsing in the default rigs.
I had no output sound after a boot.. remove the USB key and change rig solved the issue, but until the USB key wasn't removed, no way to get a sound.
Have you tried the same thing using a different USB stick?
Did you format your USB stick?
nop, just one, formated by the Kemper.
It's just random crashs, no issue today using it so.. not a major bug