Jack Audio Server multiple output ports
 

By default, jack uses 2 ports for input and 2 for output. I have a SoundBlaster 5.1vx card, and I would like to use a "line-out" plug for monitoring. But when I try to get jack to reserve four extra outputs by using the switch "-o 4", it gives me an error.

Any ideas?

Do you use qjackctl interface?

Yes, and I am familiar with the jack command line parameters as well. But more than two output channels just doesn't work when configured with either.