[RWP] Midi Sync for Compensating Hardware Latency

[Indigo]

I think this forum post might have exactly what's needed for your 
hardware latency problem.

Quote:
  Reaper midi sync latency compensation setting

Question: I recently scored a tr-727 so I synced it up to my TC konnekt 
8, which I ran
"midiTest" on, (if you don't know what it is google it... pretty 
interesting!) and
it says my midi 'send' time is less than a millisecond.
I then routed the output of the 727 into a channel running 44.1 with 2.6 
ms latency.
When I try to sync the output of the 727 to the click in reaper it is 
off by a considerable
amount ... I was wondering where the setting is to compensate for the 
latency? My
immediate fix was to nudge everything else in the project over to sync 
with it, but I know there must be a better way.
otherwise it syncs rock solid as long as I start from the very beginning 
of the track!
Answer: There's 'MIDI output offset' for every single MIDI output. A 
positive value delays
the MIDI stream by X milliseconds, whereas a negative value makes the 
MIDI to play
X milliseconds ahead.
I believe a negative value is the most usable, external gear usually has 
some latency
which you want to compensate for - the MIDI stream needs to play a 
little bit ahead
of main audio output to actually play in sync with it.
However, there's a limitation in 'MIDI output offset'. A negative offset 
of about
20 milliseconds seems to be the maximum negative offset.
If more than 20 ms negative offset is needed, it's possible to use 
ReaInsert and
it's plugin delay compensation. This is what I do. It's possible to have 
a negative
offset of several seconds.