Though sometimes it is really hard to say where the error is. Take our German cable providers for example. I like and am used to watch shows in their original language. With FOX Channel De, Syfy De, etc. that is possible. But sometimes there are just a few shows that don't broadcast the original language even on those channels. I was very frustrated to see that Fox was running a marathon of The Bridge (the original, not 'America') where there was just no sound. I thought there were problems with the broadcasting and deleted my recordings since they were useless until I found out that they were only available with German sync. Sure, this show was not an original English language show. But to give you an other example, take the Lincoln documentary (Spielberg). Same troubles. Since I allways have English as the first language on, there was no sound at all. Only after switching to German there was the German sync. So I can imagine, that listening to Audio descriptions without realising it is very frustrating.