How can i hear my TI connected directly to my soundcard? (LIVE button)

[erolz]

Hi,

i have connected a Virus TI synth directly to input 5-6 of my RME Fireface400 FW soundcard.
also connected the midi in and midi out to the midi in2 and out2 of my Fireface400.
Got a masterkeyboard connected to midi in1 of my Fireface.

When i start a new Cubase project and add a empty midi track (input masterkeyboard, output fireface midi2) i do not hear a thing...

got a sound on channel1, VC as vsti and output OUT1-2.
i do hear the USB outputs btw.

How can i hear my synth connected directly to my soundcard? What else do i have to do?
Thank you.