Is it possible to filter the autocompletebox by several columns?
And on the same topic - is it possible to use several columns in DisplayMemberPath (e.g. Artist + Song Name)?
Filtering by several columns can be achieved by overriding the FilteringBehavior class. In order to use several properties for DisplayMemberPath you will have to set DropDownItemTemplate and BoxesItemTemplate. You can find attached a sample project demonstrating both approaches.