Limit on sound length (time) on mobile?

[fitness23]

For my game I've attempted to put the entire soundtrack onto one big soundsprite. The reason being is that I've made a click and point adventure game where each room you go into has different music. Since you can't fully remove an audio file completely from the cache I decided to stay with one sound sprite that I could add markers and play on. However my soundtrack is 12 minutes long and if I try to add a marker on any piece of music after the 6 minute mark (or so) it doesn't play on mobile but it does play on desktop.

Has anyone else had this?

I think I'm going to revert back to using single music files per room. There must be a limit that IOS at least puts on audio length. They do the same for image dimensions, I think the biggest image you can load to IOS is 5000px x 5000px.