[orca-list] Setting Firefox' Audio Device: How?

[Janina Sajka <janina rednote net>]

Does anyone know how to tell Firefox which of several installed audio
devices it should use? It happens I have three installed, and Firefox
has chosen to use the second of these, but I'd like it to use the third
one instead.

I see the Preferences option under Edit, and this allows me to associate
file types with applications, but I can't find where to indicate devices
to use.

Janina