There's some weird behaviour going on with iTunes 4.6. This is specific to the song "Eleanor Rigby" by the Beatles. I haven't been listening to it for some months now, but I remember that it never sounded odd.
OK. Here is what happens: When the first verse begins, after a few second the volume of the vocals levels down dramatically, and comes back to normal after a few lines. Same happens in the second verse. This has *nothing* to do with the file. It plays well in the finder or in Quicktime Player, and reripping solves nothing.
I tried deactivating the "adjust volume" setting. No difference. I tried deactivating the "improve sound quality" setting which makes it worse: Vocals disappear completely!
Can anyone who has the song one his computer, check if this happens with his iTunes too? I never heard about any problems like that with the new version (or any version, come to think of it).