DTMF Enhancement mode was rolled out as a feature all new DCP’s manufactured from April 2022. The feature is included in DCP Software version 1.60m and later (1.60n , 160o , 1.60p …ect)
In order to roll out to older 4G DCP’s, send this SMS or scan the QR code and send to the DCP phone number to update the software to latest release (1.60p): Pin1234,p0500,devhub.avire-global.com/assets/firm/mk775/mk07758x_BOOTv100_APPv160PST.bin
The DCP should reply with this: MK-775: AC4CM10X10FX0000 P050=0,devhub.avire-global.com/assets/firm/mk775/mk07758xBOOTv100_APPv160PST.bin
Wait 10 minutes for the DCP to download and update software version.
After this, send the following text message or scan the QR code and send to the DCP phone number to turn on this new DTMF mode: Pin1234,P02000,P0436
You should get the reply: MK-775: AC4CM10X10FX0000 P020=00 P043=6
Wait for the DCP to send this SMS reply, and the update is complete.