Can't export as audio file with Ableton Live ?

Hello, I'm using the Virus TI since 1 year, and for the first time, i can't export the tracks from Virus as an audio file ?
All of my tracks are exported ( like drums etc .. ) but not the Virus i don't understand ?
When i export my song, i can see a little black or white key at the bottom of the screen.

I'm using the last version of TI OS, Ableton live 8 .. Can someone help me please ?

Thanks a lot.

Nico.

My last song i have exported evrything by clicking on " Export audio / vidéo ", it's strange !
btw thank you Roby