Have you eliminated the possibility that this errant controller (VCA filter, modulation) information is coming from a softsynth open in Sonar via a MIDI out on the synth? Anything that Sonar itself is sending should be visible in the event list on a Sonar MIDI track. But a softsynth can be the source of MIDI messages that you are not yourself entering in a track. MIDIOx should give you a list of MIDI sources in your system, and you can monitor each of them to see if any of them are active in addition to Sonar. You might also consider changing the channel on which your outboard gear is receiving and Sonar is sending so that it is only responding to a single track at a time. And of course if you are using your outboard gear in a daisy chain, it is possible that some outboard gear is sending the message down the line. Or an attached control surface or synth with a stuck switch, wheel or slider could be the culprit.

After 3 days, I'm completely stucked... Just a midi track in SONAR Platinum, no soft-synth inserted. Just the second computer's midi interface to monitor MIDI signals coming from the first computer... And SONAR keep on sending random and unwanted MIDI signals.
 
Antares sent me a new firmware that makes the unit to ignore those unwanted messages and prevent it from crashing... So I give up... The problem is still there but I get around it...
 
:(
 
Jeff

Did you ever set up the test I suggested? It's impossible to effectively to troubleshoot something with so many unknowns if you won't help us eliminate some of them. You are our hands and eyes.
 
 

Have you tried using MidiOx on the computer with Sonar to see what Sonar is sending out if anything?

If Sonar is emiting MIDI CC messages then it makes no difference what's connected to the DAW via MIDI because that will only be repeating the MIDI. So MidiOx should show it.

Also try connecting the Antares and if the CCs are being emited connect MidiOx to the relevant MIDI output port in Sonar and the MIDI inteface so MIdiOx sits between them and records everything that's going on.

Believe me, if my copy of Sonar was pumping out CC1 or 74 I'd have noticed. It isn't.

What happens if you put the MIDI Event Filter plug-in your single MIDI track and filter out everything except program changes?
 
I can't imagine a scenario where SONAR would decide to send out random MIDI data all by itself with the transport stopped.