Dear Maintainer, Piano sounds from the right side instead of the center when I play some midi files, such as "https://www.mfiles.co.uk/downloads/beethoven-minuet-in-G.mid". I suspect the root cause is 0005-fix-drum-panning.patch, because reverting the patch or commenting-out "pan=0" from bank 0 & prog 0 in "/etc/timidity/fluidr3_gm.cfg" makes piano center.
I believe that you are right that this is caused by: 0005-fix-drum-panning.patch I've just filed a related bug-report about this myself: https://bugs.debian.org/cgi-bin/bugreport.cgi?bug=999710