Another common term is "elevator music."In AE the common terms are Muzak and background music. There are other more disparaging terms, such as dentist office music, which rather adequately describe much Muzak.
I use "hold music," although I usually put a vulgar adjective or two in front of the phrase.By the way, when you phone a company and they tell you to hold on, you sometimes get music on the phone while you are waiting; can we use the same expression for that kind of music? Or do you use a different word or expression.