I need help with a different kind of export problem.

To start with, this isn't the usual 'exports sound muddy' problem. I am well aware that the result can sound different on various playback prorgams.
 
I have a project with several audio tracks. Some of those were recorded in mono and some in stereo. Likewise, the interleave settings are set to mono and stereo as one would expect. Both types of tracks however, utilize stereo audio effects.
 
When I export to any format (wave, mp3, etc), the mono tracks have their effects hard panned to center (not respecting knob value) when listening over some devices, but not the ones actually recorded in stereo, while the same exported file sounds fine if imported back into SONAR.
 
This led me to believe that there is a difference in the way various programs handle interleaved channels, so I set them all to 'on'. This changed the sound drastically within SONAR and invalidated the overall mix.
 
None of the mp3's ripped from commercial CD's seem to experience this. They sound equally well in/out of SONAR. Even on the programs that play my own mp3's badly.
 
Remember, this isn't an overall 'muddy' sound. It's only certain channels that are affected. What could be the cause/solution for this?

Thanks for your time.
 
Drew

Try setting the mono track's interleave to stereo. If you have stereo effects on them the interleave will need to be stereo for them to work properly. I always just leave the interleave on stereo. I never understood that button.