ipod touch 6th gen. Cannot Airplay Audio Books

Hi,

I recently purchased an iPod touch 6th Gen. Like my old 4th Gen. I was able to airplay Audio Books to my Apple TV 3 until last week. Now if I start a book, the time bar shows briefly, then the playback stops before any audio is heard. I can still play music no problem, just audio books will not play. My 4th Gen iPod Touch can play back fine but it is on IOS 6.1.6 & cannot update beyond that. Audio books also play fine via WiFi through our JBL Soundfly speakers,

iPod Touch 6th Gen. is on IOS 9.3.4, Apple TV 3 is fully up to date

Can anyone suggest how to fix this?