I think it's that the c64 only has enough juice to do midi follow. The clock on the behringer is known to be pretty crap and that it is what is doing timing in this basic setup. That's why I suggested I might use something like the Tr6 reissue that likely has better midi. It kind of negates the exclusive use of c64 for percussion, but does open the doors to a lot of other interesting uses.
It's basically the symptoms are wandering timing. They always fall a little out of step after a few minutes. I could see if some of that is that specific machine. I have an NTSC bread in that is pretty mint. But this PAL unit has sidFX and a bunch of other mods so.
Anyone using their retro machines to make music or for live use? I experimented with making live Acid music with a C64, using Mssiah, and a 303, etc. The timing of the 303 clone wanders sync too much as is but maybe adding a better midi clock like a modern drum machine to help keep it all synced.
Thought, opinions?
I recognize some peeps from the Flashback demo parties too.