Setting up external sound card

[Support@MixVibes]

This mean that both outputs (master & headphones) are on the same physical connectors, so you're stacking audio.

[KevMaverick]

Try increasing the number of input and output channels on your soundcard control panel. I noticed that you have front and side surround - if you increase the number of channels you will possible get a 'rear' channel.

On my set up, I have front as master, and rear as the cue channel.

Cross sees that as channel 1/3 and channel 5/6.