I'm trying to make a polyphonic version of this patch: http://www.lubbertdas.org/pd/guitar1.html (original monophonic version).

I followed malestrom's poly tutorial (http://puredata.hurleur.com/sujet-5883-polyphonic-voice-management-using-poly) and polyphony seems to be working fine.
However, for some reason MIDI notes 64 and 76 (both E) are much more muted than all the other notes. Some notes also ring out for longer than others but this isn't as important.

Any insight on this anybody please?