So I ended up figuring this out after some more trial and error. Here's what I ended up doing for those having similar issues: I thought that since all of the enhancements in that window were not checked and listed as Disabled, that there were no enhancements being applied, but obviously that's not the case (Thanks Microsoft...) Maybe this is some kind of equalization increasing the JAWS volume from zero in one ear? Who's to say. Anyways, issue seems to be resolved now. Still unsure why this only happens on our 5400s and not the 5480s or 90s, but I'll just accept a solution now that I have one. Hopefully this will save someone some headache in the future.
Hi all! We've just received a batch of refurb 5400s, and they all seem to be having issues with audio output seemingly being stuck on Mono. We're using Windows 10, but no matter what I try our users are saying that the audio from their USB headsets have a slight echo, like the sound is coming through both sides. Our org supports a large number of blind or otherwise visually impaired users, so being able to route their screen reader software into one ear without any echo is something pretty standard for us to need to set up. Here's some of the things we've tried so far: I can hear that their screen reader program (JAWS 2022) is routing the audio correctly, since I can hear the reader come through only one side of my headphones when they route sound to the left or right during a remote support session, but from their end it still plays out of both sides, though after using the routing command it does get quieter on the opposite side. From what I can tell, this isn't an issue with JAWS and all of the Windows settings that I can find are the exact same as the other models that don't have this issue.   Has anyone else run into an issue like this before? I'm going to try to see if there's maybe some BIOS setting that I've missed, but other than that I've run out of ideas to try. Any suggestions or advice is would be greatly appreciated!    
Latitude 5400s - Stuck on Mono audio?