My iOS CAPX that I've sent to you, does not use any third party plugins.
The problem is squarely due to the previous Music "work around" code.
In c2runtime.js
if (this.runtime.isWKWebView)
playMusicAsSoundWorkaround = true;
Changing to false; fixes the random crash bug. As IJCT has noted, doing this also fixed his lack of audio problems.
ie. With iOS10, there is no longer a need for prior hacks to get music to work, and the presence of such workarounds is now causing conflict.