I cured a similar problem in a lightly driven MTX, with synthetic ATX and a complete brake fluid flush - I had to insist (and literally watch) to get the clutch slave cylnder (under the dash) flushed as well. They charged an extra .9 flat rate hours, but the improvement was worth it. I assume the automatic 'adjustment' of a hydraulic clutch was 'prevented' because of the 'tired', old fluid. The mechanic was only 'under the dash' max 10 minutes. The total flush was 1 litre of fluid.
