no sound from si-bass in sonar 7 help needed

Hey everyone.I'm having a very frustrating situation over here.But still no fix.I'm using sonar 7,and native instruments.
And using a MIDI and OUTPUT track combination.
 I'm trying to add in a bass track with the SI-bass.The usual way.insert soft synth.SS options midi source synth track folder first synth and enable midi output all checked.I've tried with out the midi checked.But still I get no sound from the bass.I can click the string and let it ring out,change a setting on the midi track and the sound will magically be there,but only if I don't touch any other controls.
 It also runs perfectly as a stand alone.ONly issues once I try to bring it up in Sonar.
 I've also noticed in the soft synth options ,as I said,the instrument will play once I have the options menu open,but  as I try to enable to midi output and click ok,it never stays enabled.
Ive recorded before with the si-bass with no problems until now.Any help would be hugely appreciated.