Amp envelopes could be the culprit. Assuming that you have a PC3 series go to the original owners manual and read pages 6-41through 6-45 so that you can understand how the envelopes might be impacting the swell that you are hearing.

Thanks a lot Dave!
pretty sure you're right about the envelopes.
i suspect that, regrettably, any possible adjustment/correction
would have to be performed on a program by program basis, as
opposed to globally.
it would, in my view, be a logical and huge improvement if the
mod wheel, which is assigned to adjust swell in the majority of
the string and orchestral voices, was configured to range from
none to maximum instead of just less to maximum.
...wishful thinking
in any event, thanks again for your consideration!
Best wishes,
g.smith

If the mod wheel is assigned to control the swell then go to that assignment and adjust the mod wheel's minimum assignment range to no swell rather than something more than zero. Example, if the mod wheel's range of control is assigned as 20-127, simply change the range to 0-127. Unfortunately there is no global change, you'd have to do this on a program by program basis.

Thanks again Dave!
i can't understand why the programmers would have elected to constrain the parameters affecting swell.
why not set the minimum to zero???

BTW, i have, as yet, been unable to locate anything in setup mode that enables the adjustment of the mod wheels parameter range.

Try adjusting the program' s swell in program mode rather than trying to adjust the setup. Edit the program in program mode, find where the mod wheel is modulating the swell, make the adjustment then save the program. When you put that program in the setup the mod wheel should work as it did in program mode. What program number are you trying to adjust? I have a gig tonight and I can take a look at the program.

Hi again & thanks again, Dave,
virtually all the strings programs, both solo and ensemble, have swell assigned to the mod wheel.
by way of example you could look at program # 551 LeadTuttiMixB (or any string program in this section)
from looking at available edit functions in program mode, it looks to me as though the AMPENV page's
attack/decay/release settings may be the only way to address the swell issue, as opposed to
modifying the mod wheel parameters, which doesn't appear to be an available option.
Thanks again for your continued (and compassionate) consideration!
Best wishes!
g.smith

Dave & anyone else who may have considered this post,
as i suspected, you were right, Dave, in your first reply.
i've spent some time adjusting the multiple attack/decay
settings on all the envelopes, and i've gotten very close
to leveling the swell on held notes/chords.
a little more fiddling with them will hopefully produce
100% success.
Thanks, so much, for your helpful consideration of my
little problem...much appreciated!
Best wishes & Best of "luck" !!!
g.smith