I have a Mii Thunderbolt adaptor that I use when I'm in the office. This shows up in the Mac system report as a Generic Billboard Device. If I disconnect the device while I have a Parallels VM running, then re-connect, Parallels detects the device as a new Generic Billboard Device and asks where it should be connected, it adds this to the list of Permanent USB assignments with a number appended. My permanent assignments list looked like this: Generic Billboard Device Generic Billboard Device #1 Generic Billboard Device #2 ... Generic Billboard Device #11 Generic Billboard Device #12 I've since gone through and pruned out all below #12. Is there anything I can do to prevent this?