Hi stoiximan, using balanced vs unbalanced its a matter of audio connection on your audio interface; i mean if you have unbalanced output on your sound card, go for that; same story for the balanced one.
Just to be clear, the basic difference between balanced vs unbalanced its the number of wire:
- unbalanced (red + shield)
- balanced (red + black + shield)
I share a pdf Audio cables with most common connection, better than thousand words
About the output level, well, first of all its weird that you can use Digital Output on Analog Output (maybe some internal software…).
Output level that came from digital source (like CD) its 2 Volt, from analog source vary form type of source (200 mV for tape and turner), balanced output can go much higher and its a standard on professional studio.
So, if can go with balanced, go for it, otherwise unbalanced output have the same audio quality, just lower level
I just checked your audio interface (Presonus Audiobox. right?), from the Presonus website, and analog output are balanced; good one!