djwolf
The second I route the first instrument into a Sonar Midi track the error disappears on all instruments.  It's not a problem but it could be a clue to someone with a good understanding of this system.

The above 'implies' that you are creating your midi tracks first and then attepting the midi routing/connection to Sonar by changing something in Kontakt?

"If" that is the case (and if it is even possible ... it's been so long I can't remember)
it is the most difficult and slowest method possible.


When you load instrumets in Kontakt they automatically get midi track output numbers assigned ascending from 1 through 16. You never have to even think about that.

In Sonar:
is where you assign the destination of the midi track. ***
Point it to Kontakt and then point it to a specific midi channel.

"IF" you build a template of 16 midi tracks you'll never have to do those assignments manually.
Add the 16 audio outs to your track template and the time and work saved is well worth it.
 
***
You can point more than one midi track at a time to talk to Kontakt.
Highlight them all
Choose Tracks > Select Track Outputs > Midi Outputs (dropdown menu) > Kontakt 5 (number of Instance)
 
You will have to manually assign the channels.
That's why I suggest a template.
Do it once ... never need to do it again.

How fast is it to load a fully configured track template for one instance of Kontakt?

https://www.youtube.com/watch?v=z6e_zyHrpQA

What Sonar audio outs to Kontakt look like once we create a 16 track output template in Kontakt:

 

Slugbaby

djwolf
 
No, possibly, not at all.  All my tracks are generating sound beautifully as long as there are no more than 6 of them and none of them have any midi data in the midi tracks.  Apparently, notes are the problem.
 

If I understand this correctly, your tracks are generating sound as long as there is no MIDI information.
What exactly is generating this sound?  Without MIDI to tell the synth what to play, there shouldn't be any sound.

Once I have up to six instruments in Kontakt's multi-rack, and each instrument is routed correctly to a Sonar track, I test that each instrument is sounding by selecting each instrument in the rack and then left clicking on a note on Kontakt's keyboard.  For each instrument I see the meters on Kontakt's instrument panels and on its mixer panel respond to the note being sounded.  In addition, I see the instrument's audio track responding appropriately to the note and I hear the instrument at its full volume.
 
It is the corresponding midi tracks where the error is occurring.  If I put notes in two midi tracks all is well but as I put more data in more tracks (like 4 tracks) then I start getting no sound from tracks. 
 
 

djwolf
 
Once I have up to six instruments in Kontakt's multi-rack, and each instrument is routed correctly to a Sonar track, I test that each instrument is sounding by selecting each instrument in the rack and then left clicking on a note on Kontakt's keyboard.  For each instrument I see the meters on Kontakt's instrument panels and on its mixer panel respond to the note being sounded.  In addition, I see the instrument's audio track responding appropriately to the note and I hear the instrument at its full volume.
 
It is the corresponding midi tracks where the error is occurring.  If I put notes in two midi tracks all is well but as I put more data in more tracks (like 4 tracks) then I start getting no sound from tracks.

We're still not getting convincing confirmation that your Sonar midi tracks are correctly routed to Kontakt and that each of those midi tracks is sending to a specific midi channel.
It would also be good for you to confirm that each of your instruments in Kontakt has its own midi channel and that no instruments are on the same midi channel.

Steve_Karl
What Sonar audio outs to Kontakt look like once we create a 16 track output template in Kontakt:

 
 

But the list of names is still mangled, isn't it? The stereo pairs start nicely with the "st1/st1 R", "st2/st2 R" pattern but then suddenly change to follow the odd-looking "st6/st7", "st8/st9" pattern.
 
Or, in other words, what if I want to use "Kt. st.6: Right (Mono)"? 

djwolf
 
It is the corresponding midi tracks where the error is occurring.  If I put notes in two midi tracks all is well but as I put more data in more tracks (like 4 tracks) then I start getting no sound from tracks. 
 

What method do you use to enter the notes? Do you hear the notes sounding when entering them?
 
Are there any changes in the 4th instrument's GUI that could explain why it stops producing sound? For example, do you see an articulation change or any dynamics or expression type sliders that have somehow moved to zero?
 
It would still help to know whether this happens with all instruments or with just some. So, what happens if you replace the 4th instrument with some simple factory library synth and re-test? (Apologies if you've already answered this and I have missed it.)

Steve Karl, Let me first say that I have taken screenshots of many of your posts and linked items for reference.  I actually created 16 stereo outputs from Kontakt numbered St.1 to St.16 as you explained and you are right, it did solve the issue of addressing all the stereo outputs in the Audio track drop down menu.
 
My explanation of how I could load instruments in a multi-rack properly routed to Sonar and how I could hear each instrument when I pressed a note on Kontakt's keyboard was valid because it told me that something about the midi tracks were the problem.  When I started putting notes in the midi tracks was when I was getting the drop outs.  On my latest attempt I thought I'd solved it.  Some video had said that I had to choose for the first drop down menu for Midi input, Kontakt's "Midi Omni".  I changed that to the appropriate channel but I still got the drop out when I put a note in the 4th track (which happened to be track 5).  I'm now not sure which option is right.
 
However, while I haven't solved the problem I do think I have found the culprit - Spitfire Audio.  When the 2-note cello part on track 5 failed to play I brought up the Kontakt panel and saw a rather strange "help bubble" on all the Spitfire instruments.  I'm uploading two JPEGs to show you.  BTW, the Harp from Kontakt's Factory Sounds that was also in this multi remained fine.
 
 
 
 

 
So, After a couple of instruments have midi data in them Spitfire Audio decides that I need to come to terms with all of its controllers and settings.  I had planned to study all of that as I needed it.  Regardless, it is clear that my problems were created by Spitfire and not Sonar so I will go and plague them for a while.  If or when I get some answers I will return to this thread to explain the solution to any other Sonar user wanting to route Kontakt with Spitfire instruments.
 
thank you

It would seem that the problem has been solved.
 
Thanks to the advice here on setting up templates which did solve the assignment issues for the audio track.
 
As to the mystery of why my instruments stopped playing, the truth was almost amusing.  With Spitfire Audio comes a "help" system to guide new users through the use of these instruments.  After the first 3 or 4 midi tracks have had data placed in them a help bubble comes up on the instruments along with a midi signal setting up Spitfire's special CC controllers that allow users to affect instrument settings from within the midi track.  Useful as this is, for those that have "Zero Controllers when play stops" ticked in Edit>Preferences>Project>MIDI after the bubble appears and a play through has been completed controllers for "Dynamics" and other settings are reduced to zero.  The solution is to untick that Preferences option, drag the setting for "Dynamics" completely to the right.  You may have to reboot Sonar for this to be completely fixed but there it is.    

The Zero Controllers option is saved as part of EVERY template.  You don't have to reboot SONAR, but you do need to edit every single template to remove it.  Otherwise it will come back and leave you wondering why that soft synth isn't working anymore.  And due to how SONAR decides when/if it needs to zero the controllers, sometimes everything will look like it is working then suddenly it will stop.  Because SONAR decided that time it needed to send the zeroing message.