I've just been burned by this. I'm staying in Eastern Europe for nearly 2 weeks. Booked a place on airbnb because I wanted an apartment instead of a hotel room. It cost nearly $1500.
Out of the more than 15, 5 star reviews, some noted there was noise, but almost every single one praised the sound insulation and said "the noise wasn't a problem for me" or words to that effect.
Well, it was a total problem for me so I contacted airbnb. It wasn't an emergency so I emailed them. Their website said I'd hear back within 2 days. That would have been fine. I just wanted to know what my options were.
After 4 days (4 sleepless nights to be precise) I emailed again asking what the hell was going on. Eventually, 5 days after emailing them the first time, I got my first response at all. They said I had to speak to the host, send them evidence, etc. I told them they could shove it and I'd be booking into a hotel because they'd taken so long.
If this had been Amazon, they'd have said "Sorry there was as problem, which of these other places would you like us to transfer you to?" I pointed out to them that a) the host wouldn't be able to make the bars downstairs any quieter, and b) they'd taken nearly half my holiday to even respond. Initially I'd only wanted advice on what my next steps could be, but after dragging their feet for so long, things moved on and I booked a hotel instead.
Their whole chain of responses to me consistently read like they were passing the buck, making excuses, and generally trying to blame me for not doing research (erm, I read those 15+ reviews), or contacting the host (despite the fact I initially asked for advice). It seemed they were just stalling. I pointed out that since I'm now in a hotel, I didn't have any inclination to go to the flat and record the noise, especially since their terms say they'll only refund you for unused nights, not for nights where they were too understaffed to reply on time (they blamed the slow response rate on "there are a lot of people travelling at this time of year". Yeah, and I'm one of them).
So all things considered, I'll be thinking twice before using them again. It's a shame because over the last 3 years I've spent over $6000 USD with them and had one particularly good experience. But their whole attitude smacks of "we're just the platform, just pay our service charge and piss off".
@nnd - I can't see how it's relevant, but since you ask, I'm told I look like a character from shrek...