Playing media file AFTER other media on slide completes

Hi 

I'm not sure that the below part of Katherine's question was answered and I have the same problem.

'I've tried having it play after all the button states change to Visited but it begins playing the final audio at the same time as the audio of the last button that was clicked.'

I have a slide with 3 markers (each with its own audio) and I have introductory audio at the start of the slide. I want to play audio at the end of the slide alongside a caption appearing. I have set a trigger for the timeline to pause at the end of the intro audio but don't know how to resume the timeline once all the markers have been visited. The trigger resuming the timeline when all markers are visited, doesn't allow for the playing for the audio on the last marker.

What trigger can I create to fix this? Thanks.