You know, that's a very good question about the firmware. I have no idea how to tell what firmware revision is on the switch, since it doesn't have a serial port and can't be telnetted/ssh'd into. Any ideas there?
Also, I'm definitely the kind of guy who would stick a thermometer probe in there and maybe even wire it up to a power relay. But then that raises the questions of "where do I put the sensor" and "how hot is too hot" .
The other possibility would be to either replace the fans with ones that are purported to be quieter, or the nasty ol' hack of soldering some resistors inline with the fans' +V lines. There's not a huge amount of slack in those cables, and it's been a long time since I've done that, so it'd probably take several trials to figure out a resistance value that would be a good compromise...