WMP11: Album art not being updated after Find/Update Album Info

Generally speaking, Album Art is working ok for me. But still, a number of my
albums are not showing Album Art -- even when Album Art is clearly shown
after I Find Album Info. The "Paste Art Here" blank icon remains, whatever I
do.

Known problem? Something I can do about it?

Known workaround: manually copy the graphic from somewhere and paste it by
hand. I would prefer this to be done automatically though, how it should be
(and how it works on most of my albums).

WMP v11.0.5721.5145

Thanks,
Stewart.