No Dolby Digital on iOS 9.3.2

When I connected my iPhone 6s or iPod 5 with iOS 9.2 to the Home Theatre with the Digital AV Adapter, it perfectly received Dolby Digital 5.1 sound with iTunes, Movies, and Netflix. Now with iOS 9.3.2 it only says "PCM 2.0", and the centre and surround channels don't sound, not even the voices can be heard, only things that sound in left and right channel. With my iPod 5 with iOS 9.2 it still works.