Multitrack Playback

I have two stereo tracks in one file and wish to play back as two stereo tracks (4 channels) through a Behringer UMC404HD.

I’m getting both stereo tracks playing through Output A (1L and 2R) of the Behringer unit with no signal coming out of Output B (3L, 4R).
I want to have one stereo track on Output A (1L and 3R) and the other stereo track in the file on Output B (2L, 4R).

In other words, I’m looking for 4 channel multitrack playback. Any suggestion? Thanks in advance.

Audacity does not support multi-channel playback - mono / stereo only.
You can export multi-channel audio files by using the “Advanced Mixing Options”, but you would need to use a different program to play the multi-channel file through multiple outputs.