Sonar 7 Producer Edition, Windows XP SP3
 
Recently I have had issues with Sonar sending wrong MIDI Note Numbers to external hardware synth modules as well as to soft synths like Garritan Jazz and Big Band via Kontakt player.
I am reasonably sure that Sonar is the culprit because both external and internal synths are involved.  The behavior is random.  When I first load a cwp file, it plays OK.  If I stop playback than sometimes, not always, one or more tracks play wrong pitches (typically a whole step below the correct pitch).  This can happen if I restart playback from the beginning or in the middle.  Once it has occurred, in order to get the correct playback to resume, I have to close and reopen Sonar if the issue was with a soft synth, or power off and back on an external hardware synth.
 
(Wanted to load a PDF of my setup in case that might help, but couldn't figure out how to do it.)
 
Ted David
Washington DC

Try doubling the buffer in " MIDI buffers..prepare using xx ms buffers".
That's the most common cause of randomly skipped MIDI-notes. I'm not sure if it helps in your case.

About your system specs: Write them in your signature so they'll always follow when you need to ask soething here.

One common cause of wrong pitches is unresolved pitch wheel events. E.g.: stopping play in the middle of a pitch wheel sequence and then starting play from some other point. This can be overcome by setting "Zero Controllers When Play Stops"

I thought that doubling the buffers (I had 64, doubled to 128) would do it, but on about the 5th playback, it reverted to the same behavior - it transposed playback the notes of the trombone track (seems to be the target with this particular file) down a whole step.  Several observations.  Using the MIDI panic button eliminates it fir the next playback, but after that one, all bets are off.  Second observation: there are a lot of aftertouch events on the tracks of this composition - but I always have seen that.  Third observation: I exported the file from Encore notation program as MIDI.  That operation frequently results in stuck notes, which typically occur at only a single pitch (maybe two in a piano part.)  But the trombone part exported had no stuck MIDI notes.  Observation 4: with this particular composition, the MIDI playback is set to an external hardware synth:  Sonar track -> MIDISport  4X4 Channel C Out -> Korg X5DR.  Fifth observation: Options: Project: Zero All Controllers on Stop is checked.

Ted David

I go with bvideo- you have CC pitch events that are log jamming. How much memory do you have? sounds like more might do the trick.

There are a lot of events in the track, not pitch wheel, but mostly aftertouch.  It has been my belief that my system (see below) was sufficient for my projects.  Typically they might have 12 MIDI tracks, which are output some combination of external h/w synths via the MIDISport or internal soft synths (Garritan JABB - up to three instances: horns, rhythm, perc.)

You may have a bad cable or a bad memory module or some other problem. Are you overclocking your computer's CPU? 

I've been using Sonar to drive external synths and softsynths via MIDI for many years and have never had this problem. You need to use the process of elimination to find the culprit. Disconnect some of those synths and see if you can narrow it down to particular project or synth. I'll bet you a virtual cup of coffee that it not a problem with Sonar. 

Thanks Dave,
 
I doubt the problem is a cable because it occurs also with Garritan Jazz and Big Band.  As far as I know, Garritan simply plays samples per the MIDI instructions sent to it.  The issue seems ALWAYS to be transposition a whole step down, whether it is an external synth or a soft synth.  With the external synth, the problem persists even though I stop and restart playback.  To "fix" it, I have to power down the external H/W and turn it back on.  Its as though the synth itself is being sent a transpose command, because it persists until I reset it by powering it down.  To get the soft synth problem to go away, I quit and restart Sonar.  It always seems to play the correct pitych the first time, but almost invariably plays it wrong the next time through.
 
And since it occurs with several sources (Korg X5DR and Garritan) it doesn't appear to be one specific device.
 
It's really got me puzzled.
 

If this is just a MIDI file why don't you post it so some of us could test it . My guess is still a hidden event.
 Say you accidentally hit your transpose button on the controller and it recorded it.
I use to open my MIDI files in Cubase and things that don't show in Sonar would show there. Like PG change. Sonar does not always show all events on the list.

You said "... doubling the buffers (I had 64, doubled to 128) ...". If you are talking about the midi prepare buffer, I've heard it recommended to use 500. If your external synth is getting "transposed" until it is powered off, then it is not a question of wrong notes, but of some unexpected, or corrupted, midi data. Another experiment would be to get rid of the aftertouch messages (e.g. save to a second copy of the project) and try that way. Is it channel aftertouch or key?