Aggregate device issue OSX Renaissance and RME Fireface

Any of my fellow MPC Renaissance users been successful using the Ren with another interface by creating an aggregate device in OSX?
I want to be able to use the outputs from my MPC Ren and my RME Fireface to send audio to my mixer from the MPC VST and record back into Logic but I can't seem to get a signal from any of the outputs at all.
I can see all of the outputs in Logic but can't get any signal. What gives?
The Fireface works fine on it's own, as does the Ren, but I really want to take advantage of ALL of those outputs at once.
Any thoughts?

I'm assuming your summing through your mixer, then returning the mix back into the rme fireface ?

Not sure if logic/au plugins can do it, but you need to configure the virtual outputs of the vst plugin first to port out to logic audio tracks.. Then output those logic tracks to the physical outputs of the soundcard(rme fireface)

All of that works fine on my setup but only with either the Fireface OR the MPC Ren, not both at the same time.
What I was hoping to do was create an aggregate device between the Fireface and the Ren so that could output from both the 2 stereo outs of the Ren and my available 2 stereo outs of my Fireface.
Unless someone can prove me wrong I do not believe that there is a way to successfully connect both of those interfaces as an aggregate device.

When you say two stereo outs do you mean 4 physical ports from the ren (stereo left, stereo right, assignable 1 , assignable 2) and four physical ports from the fireface?

Yes, exactly.

i haven't got my fireface to try atm... i will however have it on wed... i could try then

Has anyone been successful at creating an aggregate device between the Ren and a second audio interface at all? Ever?

DBurkeM wrote:Has anyone been successful at creating an aggregate device between the Ren and a second audio interface at all? Ever?

Yupp. Successfully, I might add. Although I don't need it at all.

Which interface were you able to get running?