I was in a tournament recently where we had to tell a player in the group behind us to turn off his music. He had it playing through a speaker with the (presumed) agreement of his group. But his group caught up to us while we were teeing off (the hole had a short backup)...and in the middle of one of my cardmates throws, here comes the music. We politely asked him to turn the speaker off while we were throwing and anytime he came up to our group. We let him know we didn't have anything against him using the speaker, but that we were not in his group listening to the music all the time, so it was distracting when we suddenly hear it. He was polite about it and we never had an issue again.
But, yes, speakers can be annoying on the course....especially since some players forget they only got permission from their group and not all groups....so they have to make sure they aren't a distraction to others.