A regular complaint on the Sky+ forum is that the dialogue on Sky Movies channels is much quieter than that on other channels.
Films on Sky Movies usually have Dolby Digital 5.1 soundtracks. The problem is that some of these films are designed to be heard in a cinema, with really loud effects such as explosions etc. You may have noticed that the loudest bits in cinemas can be almost deafening. To keep the dialogue at a reasonable level it is mixed a lot quieter than the noisy effects. You are getting the same mix at home, where most people don't want to listen anything like that loud. The result is that when you turn the effects down to a reasonable level the dialogue is much too quiet. There isn't much you can do about this, I'm afraid: what you need is some sort of automatic level control, which I don't suppose any TVs offer. Older films don't have anything like the range between dialogue and loud effects, so that's why they are easier to listen to.
problem is actors mumbling: older films would have been recorded using
a boom mike which obviously had to be kept out of shot, so the actor
would have had to project somewhat; but nowadays scenes are sometimes
shot using radio mikes on the actor's person, meaning that the actor
can speak quietly - add a tendency to mumble to that and you soon have
dialogue which is difficult to follow.
Then there is what is called 'the director's mix', where the director, who knows the dialogue backwards, insists on it being held down with the effects - so that the ordinary punter can't hear half of it. Between both of these issues I sometimes can't hear the dialogue clearly, on a first-class hi-fi set-up. 1930s and 1940s films by contrast are always perfectly clear, because their producers knew they would be heard in all sorts of cinemas, some with poor acoustics, so every effort was made to make the dialogue clear.
Oddly enough, you are may have more
problems with the wide dynamic on Sky than on DVDs, at least older
ones, because Sky
evidently broadcast the Dolby Digital track intended for cinemas:
whereas I strongly suspect that at least some DVD issues have had the
tracks remixed to provide a less demanding sound for domestic
listening: this sometimes involves not only reducing the dynamic range
but also reducing the amount of specific sounds in the rear channels.
Blue-Ray issues seem more likely to use the full dynamic range.