few additional infos, just in case:
. I'm running latest version of MM (18.104.22.1685) and Lastfm Scrobbler;
. Scrobbler works with both iTunes and Windows Media - but not MM
sidenote: Lastfm offers 2 Windows Scrobblers (!?!) : Lastfm Scrobbler and Lastfm Desktop Scrobbler.
I installed one, then the other.
The one working with other music players is Desktop Scrobbler.
Though I wonder: which should be Scrobbling MM ? Whether the MM script is autonomous from those Lastfm tools, or interacts with one or the other ?
Thanks again for your help...