I have been doing video only drag to a music bed for trailer. After adding a music stinger to the audio bed. I could not drag video only to the program screen - I would get a hand with a circle with a slash through it. I could do a audio and video together drag to the program screen - and of course this would wipeout my audio track which I didn't want to do!.. I did something during the drag audio only to the timeline that changed some setting - but what!