I don't mean to be disrespectful, but come-on guys...
There is nothing wrong with the midi timing on the 2080, I recommend you check for problems in the rest of the system (loopback or poor ports) or perhaps the midi stream (ie embedded CCs or Sysex).

I'm running two fully loaded JV-2080s (14x SR-JV80s) plus numerous other Roland synths and samplers on 10 MIDI Ports (160 channels) in a medium-size Project Studio -- I have yet to run into ANY timing problems (unless of course I try to play 64 simultaneous tones on the same measure:beat:tick, but midi will choke on that).

David
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