Firstly I realise that this is very special case but thought it was interesting enough to post about. I’m using 4.9.2 currently but I know that it has been doing this for a while, just taken a lot of time to warrant posting it. This issue also occurs both in editor and in built packages (development and shipping).
I have disabled on board speakers on my machine and didn’t have my headphones plugged in so there were no audio devices connected to the machine whilst I was doing work. I have a few triggers in my project that are based on audio finishing playing, and they weren’t triggering the whole time that I didn’t have a device plugged in. I came to the conclusion that they weren’t actually playing at all because there is no device connected.
Kind of frustrating as I have no way of controlling that as far as I can see and also have no way of controlling whether or not people play with audio devices or not!