Thank you Karim and Jean!
Regarding Karim’s suggestion, I have tried SET-PORT and it seems to work fine.
My problem was actually with the other lisp object changechan.lisp Karim have sent me in 2015 (having the cat audiophile profile) to be able to change channels: http://forumnet.ircam.fr/user-groups/openmusic/forum/topic/voice-is-there-an-input-for-midi-channel-selection/
I’ve tried to trash all chord and chord-seq object in the patch, I tried a new patch, I even tried a new project. However, I keep receiving “function Changechan does not exist!”
I followed Jean’s suggestions. Suggestion 2 (put the .lisp file in …/OM 6.13/Contents/MacOS/Init/) didn’t work for some reason. However, suggestion 1 work successfully!
Thank you again guys!
Phivos