Hello, The following is experienced with PTE7 beta 17 I have one slideshow with a master video track spread on 2 slides. This works perfectly. Then, if I add a new video clip as follow: - as object onto a previous slide - as one single video - inside one mask container, Result: The master video track becomes mute. the new single video is correct. If I extract the single video from the mask and copy it elsewhere on the same slide (CTRL-X CTRL-V) , the master video track retrieve its audio! Jean