Star Trek: The Next Generation/Do voice recordings work?
Has it ever been ruled out that someone trying to take over the Enterprise (or other ships) can't use a voice recording of the captain etc.? Example: an enemy couldn't put together a recording of the command crew ordering a self-destruct.
I don't think that this has ever been ruled out. Given the lax security at times on even the flagship of the Federation, it wouldn't surprise me.
Actually, the Enterprise is taken over by Commander Data in "Brothers." He creates a security code, sets up cascading force fields on his route to the transporter room, and localizes command functions to the Bridge, all while speaking in Captain Picard's voice.
Since the computer accepted the orders, it either could not discern that it was actually Data speaking, or it did not care. I'm assuming it was the former.
In "The Naked Now," Wesley Crusher uses recordings of the captain's voice to order the engineers to various places, and also to "assume" command of the ship. He wasn't actually recognized as such by the main computer, but (thanks to a force field) had isolated himself in Engineering, with full access to the equipment.
In "Menagerie, part I," Spock uses recordings of the captain's voice to take the ship back to Talos IV. (Kirk wasn't aboard at the time.)
The last two aren't really examples of the computer being fooled by voice recordings, but the first one is, in a sense.
So, I think that, yes, an enemy could certainly try to take over a ship in this fashion. The problem is that security codes are oftentimes necessary, and it would be hard for enemies to have this sort of information. And it's very likely that ship commanders change their command codes on a regular basis.
In "Brothers," Data simply states (in Picard's voice) "Alpha Two clearance," when aborting the saucer separation sequence. There is no command code required, which is awfully convenient, but Data probably would have known it anyway. It makes you wonder why "Alpha Two clearance" was even required. If the computer thought that it was Picard speaking, why couldn't he just order the sequence aborted without security clearance?
Ordering a self-destruct would be harder, since that requires more than one command-level officer to initiate it, at least on the Enterprise-D. Also, command codes are again necessary.
Well, I hope that this helps. If you have any further questions, please ask.