Here is what worked for me.
Open launcher and connect to Obsidian v4 USB port and power on saber.
Click the Obsidian Soundboard tab.
Click the Format Memory button.
This opens the formatting window.
Uncheck the resize all box.
Make the changes to the sound banks.
Click the Format Memory button.
Click Yes to the warning.
At that point formatting began. Took 5 - 10 minutes.
When completed it takes you back to the main window.
Click the Sounds wizard button.
This opens the Banks Selection window with the newly formatted banks empty and ready to be loaded.
This is the process I followed. Worked with no issues. Hopefully it will work for you as well.