Hi, dunno where it might be set up wrong but I think everything is correct. But the behaviour is a bit strange. So: I have M2000 external FX and I tried to define it as External FX in Cubase. Because of I intended to use Reverb in M2000`s engine 1 I set up External FX like below:
M2000 has been configured as “Dual Input” - it means in my case its Input 1 leads only to Engine 1 which stereo output is going back to UR824 soundcard. Well - the right channel of main bus became more loud then left. So I bypassed the Engine 1 upon M2000 (not to hear the processed signal) and checked the only send signal feeded to it. It was surprise - the audio track from which the signal should be sent to M2000 Input 1 was sending the right channel directly to main bus:
So what is wrong? I did a few experiments and found if I set up the External FX as “Stereo-Stereo” configuration and connect only left Send bus to it then everything works OK:
So why the send slot inside mono audio track feed the signal not only to the souncard output defined in External FX tab but apparently to the right channel of main mix bus?
What I misunderstood or I was missing? Till the first attempt I had a really clear idea how the overall process works…but this was really bad surprise.
Thanx for any hint/explanation!
Pavel
but I think I know Cubase`s environment well (throughout the years) and actually I cannot find anything. If the M2000 is switched off (or - just to be sure - both UR824 outputs which are connected with M2000 inputs are disconnected) there is signal in right channel still - I cannot understand this… if you have at least 4/4 soundcard you can try it by yourself 
just define External FX in “Mono/Stereo” configuration and try whether you get the same result as me. Everything is based - I mean - upon FX track with External FX loaded…or there is a bug 
