It has been years since I owned the XP80, but let me make a couple of suggestions..
First, check your midi transmit parameters for the channel you wish to terminate the channel aftertouch...Look for CA[channel aftertouch]..
Second , you can turn off the recieve parameter for aftertouch on the midied sound source the XP80 is sending info to...
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Roland G70 (2007), Roland A800 PRO, MediaStation X-76....and a custom Busilacchio accordion (1964)..4 Roland Cube 100 keyboard amps (1985)..Edirol M-10DX mixer (2010).. Toshiba Satellite laptop..and Podium Pro 1205a powered speaker
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