Audio tracks

[electricsa]

I'm hoping to get clarification on how the audio tracks function.
There are spaces for 4 audio tracks.  But if I add and enable two or more of them, I only hear one.
Why are there spaces for 4 audio tracks if only one can be audible?
Thanks for any helpful explanation or guide to full explanation.

[eumagga0x2a]

In Avidemux, only the first one of all enabled tracks can be played back, there are no cross-track mixing capabilities. This doesn't affect players which get to play its output.

To find suitable audio delay for another track, make that track temporarily the first one.