I use a fireface 400 for my livesets in clubs.
Usually my laptop is connected to the fireface which then goes to one of the Dj mixer channels.
I realized that the master output of the DJ mixer shows that the sound is panned to the left.
I tried out different dj mixer channels and also different cables. no difference.. its still panned.
I guess it has something to do either with the output jacks of the fireface OR the settings in totalmix/settings.

Can somebody help me?

All the best!