If you're using the DIN sync on the 808, it won't really work with MIDI
sync. As it turns out, DIN sync cables - although they appear to be
MIDI cables - actually use the other 2 pins of the cable.
Unfortunately, I found this out the hard way. When I was syncing my
Technosaurus sequencer with a JoMox drum machine. They use DIN sync,
and when I tried to use a standard MIDI cord - no go. I had to find one
that had all 5 pins connected to get any action at all. Hope this
helps!

-andrew bunny