For interests sake (or not...), here's what I found with rhythmbox
load gnome-icon-utils
.gtkrc-2.0 file: gtk-icon-theme-name="gnome"
no icons at all
.gtkrc-2.0 file: gtk-icon-theme-name="hicolor"
play, previous, next OK - no repeat, shuffle, browse
load shared-mime-info
.gtkrc-2.0 file: gtk-icon-theme-name="hicolor"
play, previous, next OK - no repeat, shuffle, browse
.gtkrc-2.0 file: gtk-icon-theme-name="gnome"
play, previous, next, repeat, shuffle, browse OK
Even with this, some of the small icons are missing - to get all icons, delete /usr/local/share/icons/hicolor and link hicolor -> gnome