Playlists selected for updating
If you uncheck "Live updating" in the smart playlist edit screen you will be able to delete tracks from the smart playlist.
However the playlist won't repopulate until you right-click the playlist and select "Update Smart Playlist".
The only way I've found that works is to open the smart playlist properties, change the "selected by" dropdown to something other than what I want, click OK, then open the properties it again and change it back. EDIT: Apple seem to have fixed this sometime around i Tunes 11.4.
You can once again select some or all of the tracks in a Smart Playlist, then press backspace to delete and regenerate (provided Live Updating is selected in the playlist properties).
Interestingly that command doesn't do anything unless the tracks have been deleted.
Donations of any convenient size help pay the bills and defray my personal costs in keeping the site going. Note that tracks cannot be removed from a Smart Playlist which already contains every track of the library meeting its criteria--it would just repopulate with the same tracks.
a lot of vinyl and you've been cashing in all your download cards.And, the only way to change their contents is to manually edit them.However, i Tunes also gives you the option to create Smart Playlists which automatically update themselves.Specifically, it used to be that you could force these playlists to update simply by opening the "Edit Smart Playlist" window for the list and clicking OK.
As of i Tunes 8, this no longer updates the playlist.But I recommend starting at 0 – it ensures a higher turnover of new music every time you sync.