Limiting Mac system volume?

Heya, folks. I posted this in a couple of other support forums, and I figured I'd let GFF take a crack at it too.

Originally Posted by Evil Alternate CelticWhisper

Anyone know of a way to lock the volume controls on an eMac G4 running OS X 10.3-10.4?

I work IT support for a public library, and we've recently had a problem with some high-school kids coming in, turning up the volume on our public Macs, browsing to a site containing noisy Flash or other multimedia files, and walking away while the speakers blare and disturb people who are trying to read or do research (the high-school area is actually in the adult department instead of the children's department, so we have people nearby looking at business texts, consumer reports, etc.).

We've been looking into ways to limit the system volume so that it can only be turned up to a certain point, similar to the limiter added to the iPod after the hearing-loss lawsuits.

Both I and another member of our IT staff are familiar with UNIX and tweaking system files, so if it has to be done via command-line hackery, it can be.

Otherwise, utilities would be great too.

So...any help for our frazzled librarians?

EDIT: Suggestions of tying down and shit-beating the offending high-schoolers until they can't remember their own names, while unlikely to be followed, are welcome for a larf or two.

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