This has been confirmed by NH http://mediamonkey.com/forum/viewtopic. ... 93#p269693 and CJJ on SUBST drive http://mediamonkey.com/forum/viewtopic. ... 99#p269699.
CJJ has probably seen the same on MTP but this is unconfirmed.
EDIT: NH confirms on MTP:
Tracked at http://www.ventismedia.com/mantis/view.php?id=6476nohitter151 wrote:It appears to be affecting all devices contrary to my initial post. I was able to replicate this problem on an iPod (d_iPod.dll), iPhone (d_iPhone.dll), and flash drive (with WMDM plugin).