Hi! Did someone bump in to this isue, or knows solution? I use RME multiface connected through adat with behringer ada8200. In Cubase I added external instrument (hardware synth) which is connected to behringers analog inputs. So now when I open my template file in Cubase and play that external instrument I hear noticable latency in Cubase. If I go to RME mixer and just route its adat input coming from Behringer (hardware synth) directly to mutltiface outputs I can hear the sound playing correctly, without latency. So, I suppose cubase its not compensating for this latency correctly, in external instrument panel it says 0.00ms, but if I change that to any other value nothing changes 
If I press "constrain delay compensation"button the sound gets more accurate, less latency but then lots of plugins I use (waves, nebula etc…) gets bypassed. Any help appreciated!
What sort of things are you experiencing?
So you have some midi tracks and you play them and they sound out of time?
Or you’re trying to play this synthesizer but it takes too long after you hit the keys?
If it’s the former cubase should take care of that.
The ada is in sync, no flashing lights?
So if you play in real time you hear more latency from the ada than your interface?
Cubase can’t do anything about realtime latency, other than if you reduce the workload and lower the latency for tracking type of workflow, or use you RME inputs for realtime tracking and the ada for playback.
Its the first thing you have mentioned. The thing is, midi track in Cubase is being played by external synth and the sound I hear through cubase (cubase external instrument) is delayed a bit. To be sure I tried to play the same midi part side by side with some vsti and yes, theres latency. Behringer is in sync with RME and all vst channels that cubase is playing and that are going to RME multiface outputs (analog&adat) are perfectly synced. Also, as I said, if I route my adat input ( my hardware synth) in RME mixer to any RME analog output directly, theres no latency. I could record this way too, but I wanted to have my external synths go through cubase cause that way I could use eq,fx etc on those instruments right away 
Maybe also I didn’t explained my setup completely in first post : I route cubase outputs to 8 RME analog channels and 8 adat channels (which then go to behringer ada) and from there I connected all those channels to my hardware mixer. I have hook up few synths to behringer analog inputs, and they are showing up as adat input channels on RME mixer software. In cubase I choose those adat input channels to be the one for my external synth. Thanks!
The way I understand delay compensation is that it would hold everything back and give the channel with latency a little more time so it could all sync up. Seems like that’s what you need.
But then you’re going through the ada twice right?
Midi is sent to synth then audio into the ada then digital into RME then into cubase back to RME over to ada then audio to mixer.
Have you tried having the synth send audio to ada but play it back on an RME audio channel to the mixer?
See if the problem is on the back side of the signal chain.
I sometimes make graphic maps of my signal flow because it gets so complex it’s hard for me to keep straight.
Good luck!