BACKGROUND: Changing the sample rate of a multitrack from 44100 to 48000 is nearly impossible in Audition. You can change the settings via a text editor manually, but if you have an already edited sequence all the clips can be way off time and unusable. But you know what CAN easily change sample rates for audio in a project? Premiere...
I'm currenlty working on a podcast and have studio recordings made at 48000, and interviews edited at 44100. I wanted to copy and paste studio and interview edits into one timeline, and as many of you know, this is impossible if the sample rates of the multitracks are different. All the tricks or fixes I found here and other places failed because of the above issues with sync and timing of the edited clips.
But then I rememered dynamic link from Premiere and Audition.
HOW TO: I opened my 44100 project in Premiere via XML, and then changed the sequence settings from 44100 to 48000. I then sent the whole timeline (audio only) to my already open Audition project. The new timeline came in, with everything in sync, and at 48000. I can now copy and paste things back and forth as I please, with no issue!
Hopefully this can help anyone else out there dealing with this issue. It's a weird workaround but much better than ripping your hair out for hours and having nothing to show for it.