On this instruction i will tell how you can enable EVS-codec (Enhanced Voice Service Codec) on VoLTE and VoWIFI-callings when you have Qualcomm Spandragon 820 or newer modem on your Android-phone. EVS-codec offer better audio quality than AMB-WB (HD Voice).
To calling with EVS Codec, your mobile network provider must support EVS-codec. You can still enable it and see it on NSG Signaling Tab. Premium Licence required see on Signaling information. You can current voice codec during calls on VoLTE tab.
This instruction tested with Sony XZ2 and Essential Phone on Telia Finland network.
- Rooted Qualcomm Android Phone
- Platform Tools to get access modem
- QPST-application. Please find application from internet.
Please enable under Developer Tools USB-Debugging on your Android-phone. Then connect your phone with USB-cable to your desktop.
Open command line on platform-tools folder
And enable Qualcomm modem mode (most phones):
mata:/ $ su mata:/ $ setprop sys.usb.config diag,adb
on Sony phones:
H8266:/ $ su H8266:/ $ setprop persist.usb.eng 1
Now please open QPST Application and access to phone modem. Here is instruction for Sony phones. You have to get access to EFS Explorer.
On EFS Explorer you have to copy on efsprofiles/overrideconfig file to your desktop. If this file is not exist in phone, you can created new one to efsprofiles folder. Please backup this file and then modify it (Make sure syntax is correct):
Upload file back to your phone and reboot phone now.
Make call to opponent who have VoLTE and EVS-enabled. If opponent and network support, you should see EVS on VxLTE Analysis Tab. Your mobile network must also support EVS on VoLTE.
If you have Paid-version of Network Signal Guru App, you can see EVS-codec is enabled on IMS_SIP_INVITE message when you make call even opponent does not have EVS-support:
Now phone advertise to network all supported codec and prefer it:
- EVS-SWB (VoLTE/VoWIFI required)
- EVS-WB (VoLTE/VoWIFI required)
EVS-codec calls works only VoLTE/VoWIFI networks. On 2G/3G highest codec is AMR-WB (“HD Voice”).