What's the best way to diffuse noise from neighbors?

I have really noisy neighbors, well to be more precise – no sound proofing between floors. They are above us – and night shift workers so get up at around 2am and bang around literally for like 2 hours then go to work. I’ve discussed it with them and they are always apologetic and say they will try and be quiet – but it still sounds like they are dropping things loudly on the floor and moving and banging furniture around. I was up till 4am last night and it’s driving me crazy. I have ear plugs and I bought a noise machine, but nothing seems to able to diffuse the banging.
Any help would be appreciated!!!