losing tracks in mixdown -

so I posted this but not sure if in the right forum - I've got Sonar X2 and I've assigned individual tracks to buses (4); when i'm in Sonar everything comes through fine in the mix - when I mix down to stereo I've got like one bus coming through and not all the time and the others aren't there - I tried to bounce the mix to a track to see if I could do it that way - no - I changed computers and the problem is still there - I've never had a problem with mixdown before and don't see why these buses should sound in sonar just fine but then are not in the mix unless I'm not selecting something I should be - I've thought of an artificial fix, but I'm not happy that the mix is not reflecting what I've got in the file and can't understand why - even when I run a mix with the Master track soloed I still am not getting the tracks assigned to the buses - again they are fine in Sonar, just when I mix down - can't figure it out and would appreciate some insight.  Thanks.

if you are running several busses, click on the waveform preview button on the buss.  If something is missing on that buss, then there's your problem.  if it is on the preview, are you sure you are sending that buss to the master buss?  
 
I usually configure 6-8 busses (keys, drums, guitars, vox, fx...) and a master buss that they are routed to.  If you were routed to the main output and not the master buss, you would hear the stuff when you played back but it would not be in the final mix.  

I patched them to a new bus (if you mean something else by master bus please let me know) - but same result - I honestly don't know why the buses wouldn't show up in the mix if they are patched to output to the master; but anyway I'm still not getting the buses in the mix; doesn't make sense to me unless I'm supposed to choose an option in mixdown that I'm not choosing - anyway any thoughts are welcome - thanks.

This pic is from an old version of sonar, but it helps illustrate what I am saying.  Notice the vertical dividers?
the things called Arp 1 and Arp 2... all the way to the first divider (from left to right) are tracks.  The next 3 are busses (main buss aux 1 aux 2) and after the next divider is the outputs from your sound card.  
 
You want to create busses like in that middle section, then route that to the sound card output.  I like a master because I can mix the various stems more easily in groups.  
 
 

When I listen in sonar (x2) I hear the entire mix; when I mix down I'm losing several tracks - I've grouped several tracks into buses to make it easier; as I say everything sounds when I listen through sonar, but when I mix down to stereo, several channels are missing from the mix; 
 
where are the other channels going, if not to a buss? are the missing channels not routed to a buss?

Yeah this is either a selection or a routing problem.
 
Make sure that
 

• ALL of your tracks output to a "sub-buss" (e.g. guitars, drums, keys, vocals)
• ALL of your sub-busses are routed to the Master Buss (which YOU have to create)
• Route the Master Buss to your Soundcard (far right in Cowboys pictures)
• Before Exporting, either Select All (Ctrl + a) or Select None (Ctrl + Shift + a)

If this doesn't work then let us know as something else is going on
 

Good tip Aaron.
 
Any track not routed to a bus will not be colour coded and obvious to spot

Thank you for the input, you guys are so knowledgeable!  I'm going to study your comments - but I think I'm onto something in that my patching was fx*ed up - I went into console view and I had my tracks muted because the buses were sounding anyway - so I unmuted them and made sure they were patched to the buses and - there they are - pretty stupid, huh - but it is confusing in Sonar in that the buses will sound in the sonar environment even if you have your original tracks muted - they sound in the buses - but when you mix down they're not there - it seems to me that what you hear in the sonar environment should be what you will hear in mix (and I tried the mix "what you hear" option, and that didn't do it - it seems to be the default anyway) - but I am grateful to you all for your insights it's a huge help in learning my way around here - if anyone is reading this far - does anyone have an opinion about whether they like to have their tracks in pre or post when they send them to a bus?  I'm trying both ways now - thanks again.

I can count on the fingers of one hand the number of times I've used Pre.
 
Use Post unless you have a good reason not to.

rir1
but it is confusing in Sonar in that the buses will sound in the sonar environment even if you have your original tracks muted - they sound in the buses - but when you mix down they're not there - it seems to me that what you hear in the sonar environment should be what you will hear in mix (and I tried the mix "what you hear" option, and that didn't do it - it seems to be the default anyway) - but I am grateful to you all for your insights it's a huge help in learning my way around here - if anyone is reading this far - does anyone have an opinion about whether they like to have their tracks in pre or post when they send them to a bus?  I'm trying both ways now - thanks again.

There is a setting to alter pre send muting behavior.
LinkPFsendmute=1 can be set in aud.ini so you never experience that again, using pre sends.
You reach this from within Sonar environment, in some dialog.
 
Coming from Sonar 4 I was used also to never get anything from muted tracks.
 
Fade in an intro or fade out an outro can be cool using prefader sends to reverb.