AT&T VoLTE (HD Voice) on US997
Has anyone gotten VoLTE/HD Voice working on AT&T with an unlocked US997? My specific model is the LGUS997. There are conflicting reports in various forums about how to get it working. I can confirm it did work with Verizon Prepaid, but with an AT&T SIM the menu option to enable HD Voice is hidden from settings. One person on Reddit claimed he was able to get it working by getting a tech at AT&T to add the IMEI to some AT&T database of phones which support HD Voice/VoLTE. Also, supposedly the Amazon Prime version of this phone, which I can only imagine has different firmware.