Cant click on option for video sound render to .flv

When I import a .mpg to flash to convert it to .flv for progressive stream download, the wizard wont allow me to click on the volume option to get the video to render the sound option. Does anyone know why this is?

Thanks for all the friendly helpers here at the kirupa forum question board, if it werent for this site, I would of lost many clients. I admit I dont help as much as I ask but will try in the future, here one should give as much as one takes.

Adam.R