TG Gateway VoLTE fix

With the shutdown the 3G some clients may have issues with 4G VoLTE calls. Yeastar currently provides two solutions for this either by applying firmware (option 1) or AT commands suitable for any current version firmware (option 2). A future firmware will include specific VoLTE for use in ANZ regions (TBA).

NOTES: 

• Before you fix the issues, insert the sim cards first.
• It is assumed the model is TGv3 - not applicable to TGv1
• The modems should be 4G/LTE capable (modem models EC20, EC21 or EC25). To check see this KB
• The fix is persistent across reboot however if you change the sim cards or insert new sim cards, you will need execute the AT commands or upgrade firmware again!
• 4G LTE Calls need enable "VoLTE" in the GSM trunks(Mobile List->Edit->Advanced Settings->Enable VoLTE)
• In some situations you will also need to hard set the network type to '4G only'
• You may get undetected sim cards issue after you fix it the first time, just click reboot on modules once or twice, or even better - reboot the gateway.

Option 1. Firmware upgrade to 91.3.0.21.48

In the upgrade section of the gateway System>>System Preferences>>Update System Firmware you can either use this URL: http://downloads.snappernet.co.nz.s3.amazonaws.com/yeastar/TGv3_VoLTE/91.3.0.21.48.bin to download via HTTP or download it to your own internal HTTP/TFTP server.

NOTE: You need upgrade firmware twice, first from your current version to 91.3.0.21.48, then again from 91.3.0.21.48 to itself.

More info on the upgrade method https://support.yeastar.com/hc/en-us/articles/8629958998553-How-to-upgrade-the-TG-TA-TE-gateway

Option 2. AT commands for any version of firmware

Enable SSH under System>>Security Center, connect over SSH to the TG with Putty or your preferred terminal. The default SSH account is 'support', default password is 'iyeastar' and to execute the commands below for each module:

asterisk -rx 'gsm send at 2 AT+QMBNCFG=\"autosel\",1'
asterisk -rx 'gsm send at 2 AT+CFUN=1,1'