Three possible solutions I can think of...
Under AVStoDVD preferences -> Authoring/Burning you can try to remove the offending burner from the dropdown list and save the preferences as default.
Or open RegEdit and go to HKCU/Software/AVStoDVD. There is a value "DVDBurningDrive" in the right pane, you can doubleclick it and delete the burner string.
If all this does not work then there is a nifty little tool by Uwe Sieber called DriveCleanup.
https://www.uwe-sieber.de/files/drivecleanup.zip
This tool will remove all non present drives from the device tree of device manager.
Good luck
manolito