BMW M6 Sound Fix
Instructions:
Step 1: Extract the "SOUND" folder into your undercover directory
Step 2: Open VLTed
Step 3: Click file -> Import -> modscript
Step 4: Import "m6soundfix.nfsms" and press install
Step 5: Click File -> Save and you're done
Here are videos showing off both sounds:
https://www.youtube.com/watch?v=t6O6cqhwwoA
https://www.youtube.com/watch?v=VQHJJA-5v-I
Hope you enjoy!!