Ask HN: Dealing with insults from older, less capable marketing hire?

Hi guys, I'm a semi-regular at HN, and dealing with something I haven't had to before at work -- I need some advice. I'm a board member and CTO at a tech company that I co-founded. I've founded and sold (as CEO) a few companies in the last 10 years, and I'm in my mid-30s. We recently hired a 50 something marketing guy; not my preferred hire based on his skills (mostly mid-size business, no tech, no startups). We've been in an uneasy detente since he joined; his first act was to tell me to change our domain name -- mine was to mail him back and tell him he needed to work with me and show some respect, to start by not demanding I do low skill tech jobs. I work remotely, he works with in the same office as the CEO... You can imagine where the story goes from here. He recently asked for a 3x bump in his stock allocation and suggested that his salary be pegged to mine. I told him that it was absolutely not possible on the equity side, it was out of market rates for his job, and that we already had an agreement on these things. Since then it's been sulking, complaining, etc. He pulled out a real winner today when he said in a management meeting that we shouldn't show customers our new product for feedback because that's what Commodore did and then they went broke. I interrupted (see, I'm not blameless here!), and said it wasn't Commodore. He said it was, I offered to make him a gentlemanly bet, and he responded "you were in diapers." My co-founder watched in bemusement. I've made my case that I think this guy is not worth the pay and trouble internally with the CEO; while he's not a key hire, I certainly am. I have no idea what the company would do without me, but I'm getting to a point where I think that life is just too short to put up with schmucks who are rude and intimidated by a younger, significantly more successful player in their space. Since I'm remote, I clearly am going to be at a political disadvantage, and I'm not sure how to proceed: Here's my working list right now: 1) Let this guy sink his own ship by cutting all internal support out from under him -- he thinks he's so good; he can prove it. 2) Trash him on the board, and try and get some motivation to find a better fit. 3) Have a heart to heart with the CEO and tell him I'll be on my way soonishly unless this guy shapes up. All these have some obvious drawbacks; I need the income in the near-term, so I can't threaten to walk immediately, nor do I wish to leave the company our customers, or my co-founder in that situation, as it would certainly jeopardize our fundraising. Both 1 and 2 are just different politics angles, something I absolutely hate, and a large part of the reason I'm in the startup game. I would not personally allow a management team to bicker and insult each other as CEO, but I'm not in charge here, so I'm stuck to my own devices. Okay HN, pay me back with advice! I could certainly use it. Thanks in advance.