fast repetition

[Dianne Salem]

 She is unable to get good repetition from quite
>a few "popular" note  in the mid-section of the keyboard. The "other"
>tech increased letoff on at least two occasions to insure that the jack
>was clearing the hammer butt cushion for proper return of the jack but
>the problem still exists.
>        I have found, during my examination, that both the hammer return
>spring and the jack spring have plenty of kick to them. All parts are
>pinned well within tolerance and the action feels normal. Furthur, the
>regulation is pretty good.

Have you checked the balance rail pin through the key for degree of tightness?

Dianne