That suond was on compression, not while bottoming. First I thought that it's because of frame design (Big Hit 04, it has a large monocoque and I thought it could strenghthen the sound from spv valve). But it most likely was because of loosen bolt that holds shaft into the shock's body. That bolt broke apart during rebound which resulted into loss of damping and "ejector seat". So, guys, get your shocks serviced right and regularly and you'll not have any problems.
Sorry but it is. But this shock took so much of abuse that it wasn't very big surprise for me that it blew up. Besides it had a strange knocking sound from the very beginning. So it's partly my fault because i didn't service it at all.