Delay next actions until audio has finished playing

Dear all,

I'm on CP2017 and have the following issue and I'm wondering whether I am missing the obvious.

I have a slide where I would like the following behaviour:

As you enter the slide, an audio file will play (it's 9 seconds long). Once the audio file has finished playing, a video object on the slide should start playing automatically.

So I have created an advanced action that gets triggered on slide entry that looks like this:

Step 1: Play Audio

Step 2: Delay Next Actions By 10 seconds

Step 3: Execute JavaScript to start playing the video object

Step 4: Continue

This all works amazingly when I test locally (all HTML5).  However, when I play this through our LMS, occasionally it happens that when you enter the slide, the initial audio will not start immediately, presumably due to a loading and buffering issue. Which means that what happens is:

1) Slide shows, fires advanced action

2) Audio gets triggered through Step 2 in the Advanced Action but does not start playing until two or three seconds later.

3) In the meantime 10 seconds count down and then start the video object. But because the audio was a few seconds late, the audio file is still playing when the video starts.

So - I'm guessing what I would REALLY want is an advanced action that looks like this:

Step 1: Play Audio

Step 2: Wait until Audio has finished playing

Step 3: Trigger the video

However, I'm equally guessing that an advanced action equivalent to step 2 doesn't exist.

Sorry, I hope my description makes sense. Any ideas how I could work around this?

Many thanks

Martin