IMPORTANT: Sound completely broken on Fire Tv Stick (1. Gen, when transcoding sound)

I have a massive problem with my Fire TV Sticks since the new interface update! Since that, the sound is completely broken when sound needs to be transcoded (i.e. DTS)! The music sounds "normal" but the voices are unbelievable quiet and sometimes you here absolutely nothing of them.
With my Fire TV 2. Gen is everything working fine.
Please fix that very soon! Most of my movies are unwatchable now!