tamper proofing audio

[Tim Aslat]

Hi All,

can anyone tell me if it's possible to tamper-proof an audio recording
in such a way that it can still be played on a normal audio CD player?

I'm not worried about the recording being copied, but I am worried
about it being modified and want to guard against it.  Its for a voice
recorder project in a lawyers office where they want to be able to
prove conclusively that a certain audio recording was made on a
specific machine and hasn't been tampered with.  I understand that it
is impossible to make anything completely tamper-proof, but I would
like to make it at least difficult for someone to do without some very
substantial resources and skills available to them.

The recording unit is a standalone PC running FreeBSD 5.4-RELEASE, and
it would be nice not to have to change that.

Please contact me off-list with details.

Cheers

Tim


-- 
Tim Aslat <tim at spyderweb.com.au>
Spyderweb Consulting
http://www.spyderweb.com.au
Phone: +61 8 84193434
Mobile: +61 0401088479