Originally Posted by
Spector5
Give this a shot first, see if it helps - all credit goes to viperboy over @ droidforums.net:
- Improve Call Audio Quality (Doesn't seem to work if you have anything to do with Alltel!)
* Dial ##7764726 (##PROGRAM) and act as if you were going to call that number.
* Enter 000000 for the SPC Password and then tap Verify
* Tap on "04 Vocode"
* Tap on EVRC-B than Apply
* Tap the Home Screen button and the phone should automatically reset a few seconds afterward. If not, power cycle the phone
* Explanation - This changes how the phone compresses and decompressed the call audio which improves the quality.
Hopefully this will save you a trip - but personally, it sounds like a speaker issue like zerog46 said. Good luck!