If this is a time sensitive issue you might want to call Cakewalk today before they close for the weekend.
That said...
Any VST effects in the project? Try safe mode and disable/enable them one at a time to see if that's the problem.
If you are using Fast Bounce in the Export dialog try turning it off.
Try exporting using different export settings. Like set it up so you are only getting what's coming out of the Mains. Then try just exporting the Master Bus or an new bus with the track routed to it. If it's a single stereo track try just exporting that track. Might shake something loose.
Can you bounce the track? Maybe you can bounce it with the effects and everything to a new track and just access the raw wave and use that as your final product. If you need to convert it further like change the samplerate or bit depth toss it into Audio Creator or Audacity or something.
Just some random ideas. That's a weird problem. Good luck.