It works great until you hit a newer tower and your phone goes dead. It is an older, albeit clearer, codec that uses more bandwidth.
Ah you are correct. So if you hit an older tower. All I know is we have plenty of people on another forum that did it and got silence
For anyone else wanting to know this....I did this & it really works! My calls were clear before, but now if I weren't holding the cell phone in my hand I would swear I was on a landline.
Here is how you can do it:
Step 1. Dial ##7764726 (##PROGRAM)
Step 2. Enter 6 0's (Zeros) as the password & tap Verify.
Step 3. Select 04 Vocode
Step 4. Select EVRC - B
Step 5. Apply and Phone will reboot.