I’m skipping over another Ministry Pragmatics topic (Why you should use background music during social time). But I just want to focus on how you use the volume during those times.
Most people set the volume at a level where it’s just below normal talking volume, but I’d suggest you set it just above normal talking volume; make it so people need to raise their voice a bit to speak to each other.
Here’s why…

1. If the music is below normal talking volume… I can hear other people’s conversations… That makes me feel awkward they can hear my conversation, so I don’t talk.
2. When the music is low, it actually makes the room feel more empty
3. In general, most people talk in a more lively manner; with more enthusiasm, when the music is a bit louder
4. When you need to move to a formal thing, turning the music way down is the best way to bring people to attention; they all realise they’re talking a bit loud, so they stop talking, they look around, to see why the music stopped. (If the music is already low when you turn it down, people won’t notice when you turn it down)

In other words, you can either have soft music and shout over people’s conversations rudely – or you can have loud music and gather people’s attention smoothly.