iOS Starts playing music by itself

I was in a boardroom in an important meeting the other day and my iPad started playing music by itself — again. 

It does this spontaneously periodically.

Neither Apple Music nor any other app was running, so it’s the OS itself and/or something in the iPad interface that’s the problem.

This behaviour has been reported multiple times by users in the community as far back as iOS 6, but I’ve never seen a satisfactory answer.

(Unanswered question threads time out after a short period of time so we end up having to ask the same questions over and over again.)

Has anyone found a way to permanently block the OS from doing this?