Client wants to transcribe hundreds of dictation recordings made in cars. Lots of noise.
 
So need to bulk process:
  noise reduction
  split files to mono
 
Not sure which should be done first. Prolly depends upon the software.
 
Loading all of them into Sonar is not going to happen.
 
Suggestions?
 

iZotope RX has some good noise cleaning tools but don't recall it it has a stand alone versions or can run in batch mode.
https://www.izotope.com/en/products/repair-and-edit/rx/features.html 
My audio PC is down until I can get the MB replaced so I can't directly check.

Adobe Audition can do it, too.
 
Even better - because it's free - Audacity can do it as well. I haven't actually tried it so I don't know how convenient it is, but it looks simple enough. Read up on it here (scroll down to the noise-reduction example).