I was expecting someone to write before me with the right answer so
I held back, but I can no longer be silent.

The problem is that there are 7 notes that have a repetition problem
in long perforations with the chains (or 'RR tracks' as I call them).
Throw away any thoughts that it's the rolls -- it only happens on
seven notes and it's consistent with these seven notes.

So I pondered what would happen if the bleeds were clogged, and
the answer of course was _slow_ repetition, but here we have fast
repetition.  So if Fast is the opposite of Slow, then we must have
the opposite problem of clogged bleeds.

So, my first thought was that the bleed holes are enlarged.  In the
Duo-Art they're in a lovely little rail and they're plastic; it's
a possibility to check.  But I was reminded that when Aeolian built
the pianos "way back when", they sealed the pouches with egg whites
or whatever to solve porous pouches.

What happens if you have a porous pouch?  Essentially the whole pouch
(or at least its pores) become an enlarged bleed.  My diagnosis is that
the pouches are leaking (at least on the seven repetitious notes) and
need to be sealed, or _replaced._

A quick check for that is to _bypass_ the bleed.  Do the notes return?
If yes, then you've got porous pouches (or a leak somewhere else in
the line which I haven't considered).  I like this test, by the way, to
check how well the pouches are sealed.  Run it without bleeds and see
how fast a cancelled valve remains playing.  If it's a long time: well
sealed.  If instantly returning:... well, you get the idea!

Eli Shahar