Cold Case: A Question About Repeat Showings

In my area they repeat Cold Case a lot, usually 4 shows a weekend. They don't seem to be in the order they were first released, but they are played.

So my question is, when they show repeats are they intact with all of the original music, or do they have to change the music when the Cold Case episodes are repeated? I think they are still as they were when they first were broadcast, but I'm unsure.

What I am thinking is that I should buy Cold Case DVD or not. Any ideas or thoughts about this would be appreciated.
Thanks you.