No sound, or only one output

No devices are listed

TinePlayer lists the output devices your system provides. Something missing here is usually missing from your own sound settings too, so check there first.

On Linux the list comes from PulseAudio or PipeWire. A machine running neither plays through the default output but will have no list to choose from.

Nothing comes out of the second output

Three things to check, in this order:

1. The second output is a different device from the first.
2. The video actually has a second soundtrack. Open the Audio Track list for that output and ensure it has more than one track to play.
3. That output is not muted, in the volume panel or in your system.