I tested it in dc, also ch1 Atlas, not work. Something is wrong. Your party member play music (tamb for example) and you got 18% damage ?
Yes, as I said it is working in a way. It's not in the way you think.
You can only prolong the music of p/b
If raid have p/b so every member can use enhanced music. So if someone w/m play music he got 18% from tamb(example). That was the idea.