I am QUITE confused. Local Control only affects the connection between the keys of a keyboard and its internal sounds.
With Local Control 'On' when I press a key on a keyboard with its own internal sounds, the synth processes the pressed keys and produces sound for whatever preset is loaded.
With Local Control 'Off' the synth simply never knows that any keys were pressed, HOWEVER if midi capable and the host software on the computer (Sonar) is set to route notes pressed on that keyboard back to the keyboard, then the synth will process those pressed notes - NOT getting that information from the actual keys directly to the synth engine, but instead by accepting the trigger data coming through the midi routing.
SO - if you have Local set to either On or Off, it has no bearing on whether or not a soft synth in the Synth Rack will process those pressed keys.
Something ELSE must be at work to produce the condition you initially posted about.
I don't happen to use Simple Instruments Tracks, so I am not sure how you specify the midi and audio routing settings for one. If using separate audio/midi tracks instead, the routing assignments would be:
Soft Synth 'Kontakt' in synth rack, with loaded instrument
Audio track Input: Set to output from Kontakt instance in synth rack
Audio track Output: Set to either Master or some other bus (keyboard bus) that eventually routes to Master
Midi track Input: Set to omni for whatever keyboard you want to trigger notes from. (Default transmit channel is 1)
Midi track Output: Set to the Kontakt instance you want to trigger the sounds from (the desired rack instance)
So in the above, it makes no difference whatsoever that local control of the keyboard is on or off, because the keys being pressed are routed to go to an instance of Kontakt in the synth rack.
IF you are wanting to record midi for a keyboard that has its own on-board sounds, and then play back the recorded midi data and have it produce sound in that keyboard, then you DO want to change Local to 'Off'. This is because otherwise, the keyboard would be processing each key you pressed, to trigger the synth engine to produce sound, and you would ALSO have the midi data coming back into the synth through the USB/midi connection, where it too would result in a triggered note. So, you would end up getting doubled notes produced for each key you pressed, which is not desirable. By turning Local to 'Off', for this setup, you eliminate that undesired note doubling, because the synth engine would no longer process the pressed notes directly, but you would still get sound properly produced by the synth engine, because it would still be receiving trigger data for the pressed notes through the USB/Midi connection from Sonar to the keyboard.
For the above setup, your assignments would be something like:
USB/Midi connection between computer and keyboard
Audio track Input: Set to whichever port(s) your audio output from keyboard is using to connect to audio interface.
Audio track Output: Set to either Master or some other bus (keyboard bus) that eventually routes to Master
Midi track Input: Set to omni for the keyboard with its on-board sounds you want to hear
Midi track Output: Set to the keyboard with the sounds you wish to hear and record sounds from. I haven't recorded any external synths in years and years (10+), so cannot immediately recall if you set to a port or to that keyboard, but in any case you are routing the midi data back to that actual keyboard so that it can trigger sounds for whatever note data it receives.
Bob Bone