If the receiving side doesn’t support the DTMF payload type of the Snom M900 device, then it may not be able to communicate DTMF to the recipient, as it lacks the ability for asymetric payload type.
For example, if Snom M900 has payload type set to 96, but recipient side responds with payload type 101, the device will still attempts to send DTMF with payload type 96, which may cause DTMFs to not be acted upon.
