Hi Yarden,
The mixer certainly shouldn’t be freezing when trying to format a drive, I’ve also not seen that before.
Please forward a link to a video in a ticket at support.allen-heath.com so that we can look into this for you.
We also have a user generated list of compatible drives available here: https://allen-heath.com/usbdevicelist
For recording and playback, I recommend using an SSD or HDD style drive as most stick/flash stlye drives are suitable for this task.
Thanks!
Alex