For only $150 I will disable your Onstar.
I already have the speed pulse wire and mike disconnected on mine, plus a new upgraded sound system thats not tied in to it.
Of course pulling the fuse would work but on some new cars it affects the operation of the engine controls, limit the input and degrade its wireless connection.
How much to disable the nagging wife sitting next to me when I drive?
Just a fuse on mine. I pulled the one on mine many months ago.