75mm focusing noise: normal or not?

I just received a 75mm. The sound it makes when focusing is louder than I expected. Compared to the Olympus 45mm which I have, it's higher in pitch (kind of "whiny") and subjectively a fair amount louder. It's not so blatant that there's obviously a problem, but I thought I should ask about others' perception as long as I'm in the exchange period. I made a little video to try to demonstrate the sound compared to the 45, though in the recording it's very hard to hear the 45 at all.

http://www.youtube.com/watch?v=_2UzlyK2QEg