Running out of ideas. Did you check your accessibility settings, just in case?
I would try changing every possible value for the dock, disabling the dock background as a starter, and see if those changes apply or leave the dock unaltered.
I have tried everything you great people suggested but to no avail. Life is too short to spend time on somthing so trivel as this.I really appreciate all of your help.I will just live with it.Thanks very much.