VST synth HAlion1 - No sound


Hopefully someone can help me, I have Cubase AI 5 and have purchased the synth add on (HAlion 1) I am using a Yamaha n8 mixer and a Roland S10 as the MIDI keyboard connected to the mixer.

As I play the keyboard i can see the VU meter pulsing in Cubase input and the Halion 1 panel L.E.D. flickers when a note is played but cannot hear a sound.

The output routing in Cubase is configured to the n8 monitor circuit.

Can anyone help me please?

Thank you

Nik Bradbrook