When working om site the chainman was supplied by the contractor. He became increasingly impertinent (cheeky, reading through private files, etc) so I waited until I heard him creeping into the next office to do a bit of eavesdropping. I then made a fictitious phone call to head office. Said that we had given him every chance to straighten up but we really would have to be looking for a replacement and so on. Ten minutes later he came in all osbequious, asked if I wanted a cup of tea, car washed or anything at all? Kept him quiet for a couple of weeks. Let your whiner 'accidentally' overhear something and he will believe it.