I'd agree - if it was a regular thing, then that's different. Personally, I would prefer our neighbours didn't do karaoke when they're drunk but they are definately having fun and I would much rather that than hearing people argue. Having said that, the most irritated I've been is when they played the recent royal wedding at 500 decibels so they could hear it in the garden. Completely spoiled my morning/ afternoon plans and I ended up going out, rather than having to put up with it. I hope you know who you are and don't do it again.