To tell your coach they're not cutting it anymore?

Maybe a little background will help....

I hired a coach for $350 a month (ouch) which includes an online daily log, training schedule, email contact (as necessary), an annual training plan, and one hour of phone consultation a month. However, I just don't connect on any level with the chap. He's highly competitive and on "training rides" they become interval sprints and excuses for why I beat him (bad hip, shoulder, leg, hamstring, bike, etc etc).

We don't talk on the phone because I find the conversations to ramble and go in circles. Simply, I just don't connect with the fellow and want to fire him in the most diplomatic way... any suggestions?

Thanks a million.