"Max bitrate" doesn't appear to be honored

[Sporkman]

I'm setting "max bitrate" on both a per-user basis and on individual "player" basis as well, but whenever I play a song either in the web interface or on z-Subsonic, it shows the bitrate as much higher than the constrained amount.

Am I misinterpreting the "max bitrate" setting, or is it simply not working for me?