Can only get default player

What seems to be happening is that at line 1362,
$player = audio_get_players('name', $playername);

nothing is getting returned. The value of $player is empty, though the value of $playername is correctly set.
I don't understand what's going on in the function audio_get_players to try debugging any further.

I just wrote a really long reply and Drupal ate it because my login cookie had expired :(

Basically, that function was returning false.
I chased things around, and eventually found that the fileformat for the node wasn't set.
Using phpmyadmin I found that this simply wasn't set in the 'audio' table -- the field for that node was empty.
I tried creating a second audio node, and this one worked. What had changed was that in the meantime, I'd installed the getid3 library.
I removed getid3, created a 3rd node, and this node had the original problem.

So the cause appears to be getid3 not installed. But the audio module doesn't state this as a requirement.

Correction -- the Audio getID3 *module* needs to be enabled to fix the problem.
In other words, without that module, audio.module doesn't seem able to detect the format of a file.

I don't see where to specify it manually on the add audio content page.

Is there something about this in the documentation?

There's no format property when I create a new node. Only when I edit it.
This means that unless you know (ie, unless the documentation covers it), you can't find this -- I didn't.

I would recommend:
- warning on the players selection page that without audiogetid3 enabled, you may only get the default players unless you manually specify format. I tore my hair out changing the settings here and getting no change of audio player.
- *strongly* suggesting audiogetid3 in both the module admin page description for audio.module and the documentation

Could this be reopened please?
There's no bug in the code, but there are omissions in the documentation. That has the same effect as a bug: the user can't do something they want to do.
I lost about a week trying to figure this one out, so I really think it needs addressing.