EC25-AUX (EC25AUXGAR08A03M1G) incoming calls show "User Busy" - Intercom/Door Phone

IoT Modules LTE Standard Module
1

I have a Quectel **EC25-AUX** module (Firmware: **EC25AUXGAR08A03M1G**) installed in a cellular intercom / door phone system in New Zealand.

After the 3G shutdown, the module successfully registers on **LTE Band 28** (Spark network) with good signal, but when anyone calls the SIM number it immediately returns **“User Busy”** on the caller’s phone.

The module responds to AT commands and I have already tried:

  • AT+CLIP=1, AT+CRC=1, AT+QTONEDET=1, AT+CSNS=1, AT+CBST=0,0,1, etc.
  • Forcing LTE only with AT+QCFG=“nwscanmode”,3,1

DTMF detection works, but the device never answers incoming voice calls.

Could you please provide the **latest firmware** for EC25-AUX (or a newer GAR version) that has better voice call handling for intercom applications?

Thank you!

Les

2

Any admins that can help on this please will be much appreciated.

3

Hi there,
Attached is the latest FW version
EC25AUXGAR08A15M1G_A0.302.A0.302.zip

Please take note on below notice:

  1. The current firmware version supports Secure Boot and Secure Debugging.
  2. Croos-baseline software version update is not supported. For EC25AUXGAR08A15M1G, “R08” represents the baseline information.