Read() responses returning 'A'

Hi All

I have a IVR setup for a survey and all the calls are to mobiles.

I have noticed that I am recieving a lot of read responses from the IVR as:
[*] logger.c: – User entered ‘A’

The reported case was that the offending Mobile is a Nokia 5800.

What I would like to know is, has any one seen this behavior before, and is there anything I can do to prevent it?


As well as 0123456789* and #, DTMF also has A, B, C and D.

Assuming the phone hasn’t sent it, the A could be generated when the GSM to PCM/analogue conversion is performed by the mobile network, or wherever the DTMF decoding is done inbound to your system. If you use a SIP provider, this could be as far out as them - you need to provide more information to narrow this down.

If you have SIP delivery of the calls, it would be unusual for Asterisk to do DTMF conversion, and trying to force it might well lead to unreliable decoding.