You'll need to remove the DRM. For this
you must install the deDRM plugin from here:
https://github.com/noDRM/DeDRM_tools...es/tag/v10.0.9
and customize it with the serial number of your Voyage.
Unfortunately the DRM is removed on import, so you'll need to remove the files from Calibre and import them again after the plugin has been installed. You can keep your metadata - just save the files outside Calibre using the Save to Disk feature (never do anything directly in the library folder - that will mess up the database), remove the formats from book entries (this leaves the metadata intact) and add the previously saved files again to the relevant book entries.