Just as the title states, I can't get the new Apple "Trailers" app to output sound via the speaker. YouTube videos work. So do other QuickTime movies, web videos, etc. I tried multiple trailers and none of them output sound. Speakerphone works just fine as well. If plug in some headphones I get sound, but in the absence of headphones there is no sound. Is this working as intended or is it just my iPhone?