Hi folks.  I have Sonar 8.5 and haven’t had a problem with it until yesterday.  Over the past few years, I’ve recorded several multi-track songs, always making a rough mix of an individual tune at various stages by exporting the song to a MP3. I can then listen to the song in the car or on my phone to hear balance, etc.
 
When I export, I always select all of the live tracks and then use the setting in the “Lame” MP3 software that says something like “what you hear”.   In the past, the MP3 sounds exactly like what I’m hearing through the speakers before I export. 
 
However, now on one song I made a mistake and exported just two tracks (I had soloed the acoustic guitar tracks before exporting).  No problem, I went back and un-soloed the AG tracks so the entire song was audible.  However, the export process is now only picking up two of the 25+ tracks (just the acoustic guitar).  I have double/triple/quadruple checked to make sure that nothing is on solo mode, that all tracks are routed to the Master outs, that all tracks are “selected” when I export, etc. 
 
I have rebooted the computer a few different times, but that doesn’t seem to work.  I’m using Windows 7 and I have the 8.53xx version.
 
Any ideas?
 
Thanks.
Don

Did you try exporting to wav and then converting to MP3? That's not a solution to the actual problem, but a temporary aid. And if you can export a wav, then you know the project isn't corrupt.

Did you try selecting nothing, which equals to selecting everything?
Did you try toggling solo mode on all tracks (I don't know if it makes any sense, but I would try  :o)

Have you tried using Master Bus as the export source (assuming you have all tracks routed through Master Bus which is the "standard" routing)?

Quick way to test your routing is to mute the master bus. Anything you still hear playing is routed directly to the main outs rather than the master.

Don't know why but unless I select "none" I have weirdness from time to time. So It
s always  "Ctrl-Shift-A " before export for me, Has worked a million time now ,, well maybe 300. :) 

Thanks everyone for your comments.  Here is what I tried:
 
·         Soloing all of the tracks and then encoding to an MP3 - no luck, still get just the two acoustic guitar tracks
·         Creating a wave file - worked perfectly, and the wave file sounds perfect with all of the instruments
·         Importing the wave file back into the project and then soloing that wave track to create a MP3 - no luck, still get just the two acoustic guitar tracks
·         Importing the wave file into a completely new project, but naming the MP3 the same as I wanted to name it when was mixing down from the old project - no luck!  Still get just the two acoustic guitar tracks! 
·         Trying again to create a new MP3 from the wave file - BUT using a different name for the final MP3 - works fine!
·         Going back to the original 20+ track song but use a different song name for MP3 file – works perfectly – I have a great sounding MP3 but with the wrong song title. 
 
So, if I change the name of the song then I don't have any trouble.  It's as if the MP3 encoder has cached my two acoustic guitar tracks and it keeps using those cached bits every time I try to encode a MP3 with my song title. 
 
Any ideas?  Do I need to uninstall the MP3 program and then reinstall it?

To bitflipper's post - yes...mutted the mains and that mutes everything - so all of my channels are going through the mains.  So it seems to be an MP3 encoder issue.  :-(

Thanks.
Don

You just reinforced the reason I always use mastering software ( Wave Lab)  to encode.  

Have you tried deleting the previous MP3 before attempting to re-encode? If your subsequent MP3 files were somehow being created somewhere other than where you expected, maybe you've been playing the same original file over and over and wondering why it hasn't changed. 

This sort of thing happens to me occasionally when I'm sending executables to QA for testing - the tester says "nothing changed", because the new version didn't overwrite the old one or was copied to the wrong location.

To Cactus Music:  it seems like the Lame encoder is pretty well integrated into Sonar, so that is the reason I've been using it.  Hmmmm....

To Bitflipper:  My naming convention for rough mixes is something like this: 

• Liquid Glass B1.0
• Liquid Glass B1.1
• Liquid Glass B1.2

and I've never had a problem with adding a different number at the end of the song.  However, the way i got this to work was to name the song "Rough Liquid Glass B1.2", and the "Rough" word seemed to break the cycle. 

Interesting....and frustrating. 

I just overwrite the old versions, why keep something you didn't like? 
I've never exported as MP3 but it must work the same way. 

I have a folder called "Mixdowns" I direct my exports to. 
If I'm not happy with a mix I go back, make changes, and export again. I select that song from the list as I go to save and click so it shows in the file to be saved dialog box, when I hit save windows asks if I wish to overwrite the file. simple.