Version:           2.2-GIT (using KDE 4.3.0)
OS:                Linux
Installed from:    Ubuntu Packages

How to reproduce: 

Put an audio CD in your cd drive.
Start amarok
Go in the Local Music part of the left panel
The Audio CD is listed, as well as the Local Collection
Expand the local collection by left clicking once on it
Clic on the '+' sign next to one of the artist (in your local collection).

--> The audio cd treeview expands, as well as the selected artist treeview in the local collection.

Other behavior :
Put an audio CD in your cd drive.
Start amarok
Go in the Local Music part of the left panel
Left click on the Local collection
The audio cd treeview expands, as well as the global artist list in the local collection.

Things that might be relevant: 
My collection is sorted by artist/album 

Expected behavior : 
The audio cd treeview should not expand when using the local collection.

Here is the output when clicking on the '+' sign next to the artist in the local collection  : 
QPainter::begin: Cannot paint on a null pixmap
QPainter::translate: Painter not active
QPainter::end: Painter not active, aborted
amarok: [CollectionTreeItemModelBase] VA node for collection  "AudioCd"  expanded