I haven't torn it apart yet to see what its doing. I haven't noticed any ill effects with the phone in the last few minutes. If you have a nandroid backup of your current install, you can fall back on that. I'm on NC5, stock, rooted, and twrp.
Looks like it injected a modded mixer_paths.xml in /etc
Update: Over twelve hours later, no adverse behavior noticed yet.
The flashable file in post 8 is a stock sprint XML file with the needed changes from the modded post. I flashed that file and recording still works. I don't use a wired headset so I can't confirm the outcome. The poster in post 8, I'm sorry, I'm on a mobile, forgot your name and can't see it when posting with XDA app. Special thanks to you for your help and running a file comparison, adapting the needed changes into a sprint original file, and packaging it into a twrp flash! Thanks leond!