Gary, we have noticed the same thing. The background noises and music are so high that you can't hear the dialogue. It's a waste of time for the actors to learn the lines.
Also, it seems like in most drama shows, the actors are always walking or running from place to place and you can't understand what they are saying. "West Wing" was a prime example of that, but now it seems to have infiltrated many shows. We enjoy the new "Hawaii 50", but it is very hard to hear and understand some of the dialogue.
Commericals are another thing. Not only are they gross and disgusting, but they are so loud that we can't hit "mute" fast enough!!