Hi
My problem is that I created a really simple FCB1010 patch (using it's software editor). All the patch does is switch my SwitchBlade to program #1. The SwitchBlade is on MIDI channel 5, and the Eventide is on channel 1 (i.e. MIDI device ID set to 1). I do not (purposedly) send any program control or any MIDI info to the H7600, only the SwitchBlade. However, and in fact regardless of what device ID I assign to the H7600, this totally simple patch does send some MIDI info to the H7600, resulting in a change of preset to number 12 (Thru). I don't understand why. Overall, my 7600 is part of guitar rack MIDI chain that includes the SwitchBlade, and 3 other rack units set to different device ID's. All are connected via MIDI THRU. Is it possible that one of the se units, including the FCB1010 sends some MIDI message to all device ID's? I'm kinda stuck right now, because I can't use the pedal at all to control the H7600. Help appreciated. 
Kofi

Attach a copy of your sysex so we can look at it.

Did you turn off Omni mode on the H7600?  No matter what you set the Base channel to, Omni mode forces it to accept MIDI on any channel.  It must be turned off for your setup.

Did you set any other MIDI channels?  Apparently the H7600 lets you set a different MIDI channel (including Omni) for each control, but it ADDS whatever number you set to the base to get the actual channel!  This is the oddest MIDI setup I've ever heard of.  And the manual doesn't say whether the offsets can go to zero!  So if your Base channel is '1' and your controller channel is '1', that controller receives on ...MIDI channel 2!  How do you set them to all be the same channel?  Hopefully they go to zero so they can all be the same, because it would be insane otherwise.

Thank you Chrisw for your detailed answer.
Kofi