Everytime I try to preview a video clip I get the error message "An error occurred while starting playback, an invalid device was specified". When I click details I get "The playback device does not support the current output format, the playback device does not exist". I checked to make sure the external monitor button was not on, it isn't. I am fairly new to Vegas, but have done some stuff with it before. I have Vegas Movie Studio 9 Platnium version 9b. Everything worked fine up until I updated the software. Any help would be appreciated.