Hey! My disturbingly loud W550 got louder..lol.
Tested succesfully on W550i.. slight increase in external speaker volume.. good change on the earphones.. not too sure about qualityt hough.. needs more observation :)
EDIT:HEY!! does not work when the phone is open!! x-( Any solutions?? Will the W880i original acoustic driver (posted previously on this thread) work for me W550i?