It depends what is meant by background music. Source or incidental.
Too explain the difference, source is where it is really happening in the scene so characters would be able to hear it*, maybe even comment on it like a radio, CD player, jukebox.
Incidental is when it is external to the fictional universe, the characters can't hear it, it is purely there to evoke emotions in the viewer, almost to manipulate us into feeling an emotion if the actors or writers aren't up to the job by themselves.
Sometimes they z2 can merge as happened with emmerdale last year. The 'Summer Fate' episode started with 'Dream a Little Dream of Me" playing in an eerie, ghostly, almost sinister fashion over shots of the circus but after 20 seconds or so, it cut to Debbie's lounge where we heard it was playing on the radio.
Much as Iu love incidental music and do feel it has made a lot of scenes for me in shows like Dynasty, Dallas, esp Knots Landing or even Doctor Who - it does put another barrier between the immediacy, and so reality of the drama. For that reason, as i want my UK soaps to be as realistic as possible, I say no to incidental music but yes to source music which can be used as effectively. One example would be 'Pretty flamingo' plaing on the vic dukebox as Linda was raped. That worked because we as the audience knew it was her and Micks song so awful for it to be played as she was raped, but also we knew that she heard it so it could never mean the same thing fcor her again - never just be her and Micks song as she would now also associate it with the rape.