I have no idea what might have prompted this, but just recently, the audio clips in my movie file cannot be moved by clicking and dragging the mouse on them, as I was able to previously. Trying to do so simply shows a cursor icon with a circle and line through it.
I have tried toggling the "lock" icon on the audio layer, but it doesn't seem to have an effect. I can still delete audio, resize it, and modify the clips in various other ways, but it won't let me move them.