I would have a serious problem with that. You're neighbours and you put up with eachother, you hear eachother moving around and if you shout, but they're being really inconsiderate, as music simply does not have to be played that loudly - ie loudly enough for your neighbours to feel and hear every word. I wouldn't care what time it was. I do not want to listen to someone else's music. It's a violation of my personal space having music on when I don't want it to be on. They don't have to have it on loud enough for you to hear it, so why are they doing it? Do they think you LIKE hearing that fuzzy, banging s*** through the walls as some kind of soothing background sound?? It's a basic matter of consideration; you don't make your neighbours listen to YOUR music.