ProTools 10: MIDI + Delay Compensation madness

[maxx.monopoli]

Hi,

recently I've set up a new PT10 HDX rig.
While I've been mixing with PT since almost 10 years, now I'd like to switch from Logic to ProTools for EDM production too.
I'm experiencing a crazy issue with MIDI timing: when delay compensation is on all MIDI messages to external MIDI devices (synths, expanders etc..) are played way earlier than the correct timing.
It seems that PT is applying a negative delay to the MIDI tracks equal to the compensated delay. All notes are way beforehand than expected.
My MIDI interface is an Unitor 8.

Any idea/advice?

Thanx,
Maxx

[Borg]

What is your H/W Buffer Size, and what value do you have in the Global MIDI Playback Offset?

[maxx.monopoli]

Hi Borg,

Buffer size 512, MIDI Playback offset 0.

I think this has to do with the concept behind the way PT manages delay compensation for MIDI. From the manual I understand that it is conceived to compensate delays in case you are "live recording" midi parts: once you've recorded the system will anticipate the take in order to reproduce it exactly the way you performed.
But if you draw parts from scratch or quantize them the whole PT concept is not working anymore.