Apple Logic Pro /LogicExpress Discussion

After making the big move to OS X (10.3.9) and Logic Pro 7.1, I've recently added a Logic 
Control to my studio, which necessitated the purchase of a second Unitor 8MK2. I use a lot 
of outboard synths (I don't use softsynths much) and needed more MIDI ports.

Here's the problem I'm having:

Whenever I move a fader to control an outboard MIDI synth, the synth on the 
corresponding port of the second Unitor 8 drops notes or behaves erratically.

For instance, I record a melody on my Waldorf Microwave (which is on port 3 of the first 
Unitor 8). Then I record a 16th note pattern on my Roland Jupiter 6 (which is on port 3 of 
the second Unitor 8).  I play the sequence back - Both instruments play together with no 
problem.

But...................When I move the volume slider (or pots if they're set to control volume) on 
my Logic Control for the Microwave, some of the notes of the Jupiter 6 drop out!!  

I've reproduced the problem with other synths that reside on the same ports of the 2 
opposite Unitor8's and doing so produces the same MIDI drop-outs.






I've installed the latest 1.7 driver for the Unitor 8s and the Logic control is running 
firmware 2.1.2. Both Unitor 8's are connected to separate USB ports on the back of my 
Dual 800 G4 Quicksilver. 

In the AudioMIDI Setup, both Unitor 8's show up separately and I've cabled my synths 
appropriately (I have the Logic Control cabled to Port 8 of the first Unitor). I've unchecked 
all Transmit and Receive channels that I don't plan on using other than the Logic Control 
and my samplers (I only use between 1 and 3 channels for most instruments).
In the MIDI environment, I've confirmed that each synth/sampler is on it's own dedicated 
port/Uniitor 8. 

I have unchecked the Program, Volume and Pan boxes for each sub-channel of each MIDI 
instrument. 
 
I trashed all my Logic prefs/Autoload and ran the Logic Setup Assistant from scratch. 

Can anybody explain why my Logic Control is causing notes to drop? Better yet, does 
anybody know how I can fix this problem? Feedback is much appreciated!

Kind regards,
Alex Gardel