Seeesh, the adapter and y cable costs like $10 + or 20% of the Z2200.

The Z came with the y cable with 2 pairs of rca cables but the behringer mixer main outs are 1/4" phone plugs (I assume mono).

Currently I just connect the 3mm male logitech with a adapter to a stereo 1/4" male to one of the main out (R) and the fader does not seem to be working. So, I guess I have no choice but to spend the $ to get the new adapter and y-cable !