C2 had a workaround for sound and music to get it compatible with Safari based export (Cordova on iOS) due to changes in iOS8 and 9. It's just now no longer compatible with iOS10.
IJCT
Music works for me. Make sure it's in the right format, not .ogg in your iOS export else it won't play. What does not work with this "hack" of the workarounds is the volume controls. Everything plays full blast and users have to control the volume via their main device master volume.
yes is m4a, do you put your music on the music folder or in the sounds folder on c2??? maybe is that
UPDATE: YES!! IS THE FOLDER!!! the music folder doesnt work anymore on ios10, i changed my music from the music folder to the sounds folder on c2 and now is fixed!!!