I just started a postdoc. I finished my PhD in 2014, so have been around the block a little bit and have a book coming out next year; the postdoc will, I hope, let me develop a new project that'll become the second book. Amongst my new colleagues are a couple of other postdocs at around the same career stage, and a couple who're fresh out of PhD.
And one of these is the mansplainer from hell. Everything that comes out of his mouth is 'advice'. Except, it's really bad advice because he doesn't seem to have got his mind around the fact that the PhD is over (the rest of us have moved institutions; he's stayed where he did his PhD). The first time I met him he launched into a monologue about how awful the faculty are, how much they dislike each other, how they have petty rivalries ... and when I scraped my jaw off the floor (because I thought this was incredibly unprofessional) and said weakly I'd been looking forward to getting to know the community, he replied 'look at the PhD students ... that is your community'.
Since then he seems to have made it his mission to tell me how to get on in the department, complete with helpful hints, like the fact I should, apparently, time seminar papers to end within the time limit, and should avoid reading in a monotone. 
I (and the other female postdoc, who gets the same treatment) have tried quite bluntly saying we know this stuff already. He is impervious.
What is really starting to get to me is that he does this in front of everyone - students and staff - and so I am constantly having to correct people who assume I'm a new PhD student, and it's making it awkward to network because I'm perpetually having to deflect conversations where people want to give me advice about revising my thesis or getting my first publication out. As you can imagine, I am getting very quick at jumping in to introduce myself first.
I know this will all shake out before long, but right now it is depressing me. Any thoughts? Care to share about your pet faculty mansplainer?