Why do some Programs or Combis have the sustain pedal disabled? The A001 AcousticPianoAT patch is a good example.

The reason is that the programmer of the patch decided that when
KARMA is active, the use of the sustain pedal caused objectionable
behavior. Or, the sustain pedal is programmed to do something else (like
activate the Note Latch function in Dynamic MIDI).
In the case of A001, I wrote this patch, and I agree in retrospect that the
sustain pedal should be active. I didn’t like certain things you could
make it do with the KARMA function active, but now I believe that it is
more normal with it functioning normally. Fortunately, it is easy to
change:
(6.1-5) [Menu]-[KARM]-[RxFilter] -> Damper CC#64 -> set to On.Here, in A001, we can see that “Damper” (CC 64) is OFF. This means
that when KARMA is ON, the Damper will not be echoed through (and
therefore will not work). Set this to ON and resave the Program, and it
will work in a more normal fashion.
In a Combi, it is a similar operation, except you can control the Damper
for each KARMA Module separately.
Note that changing this setting doesn’t always change the damper
operation, because this particular setting only affects what happens
when KARMA is ON. If the Damper is disconnected when KARMA is OFF
(also), then you must go to another place:
(4.1-2a) [Menu]-[MIDI2]-[MIDI2-2] -> Damper CC#64.
Also note that if you are doing this to a Program or Combi, you should be
aware that the Damper may be assigned in the Dynamic MIDI section to
perform some other operation. You should check this and make sure
there is not a conflict – you may want to remove the Damper from
Dynamic MIDI in this case:
(6.4-3) [Menu]-[K RT]-[DynMIDI]-> Source -> locate Damper CC#64.

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