Sometimes people are just very focused on their day-to-day stuff that they just want your call to be a very quick business interaction. In those cases, if you say something and they didn't really appreciate it, you should just accept it and move on.
I also feel that CSMs should be true to themselves. If that means you love to crack jokes, you should continue doing that. But if you don't, there's no need to force yourself. If you do, it will come out flat and things are now worse.