asterisk users - Feb 2005 - Asterisk, inband DTMF send by a GSM mobile

Hi all,

I use a GSM device to send dtmf on my asterisk system (via SIP).
the codec I use is ulaw (or a-law).
dtmf mode is INBAND.
relaxmode is on.
but most of the case,  I 'missed' some DTMF or
I 'double' one.
as anybody as seen this before?
is there any way to prevent this


thanks

On Feb 15, 2005, at 10:09 AM, Florian Lefeuvre wrote:
> Hi all,
>
> I use a GSM device to send dtmf on my asterisk system (via SIP).
> the codec I use is ulaw (or a-law).
> dtmf mode is INBAND.
> relaxmode is on.
> but most of the case,  I 'missed' some DTMF or
> I 'double' one.
> as anybody as seen this before?
> is there any way to prevent this
>
I suffer from this problem all of the time but I'm configured for 
out-of-band dtmf on the asterisk side thanks to IAX2 trunking. I think 
the problem is GSM or maybe cell phones in general. I know this has 
been discussed before.

-mark

--
Mark Eissler, mark@mixtur.com
Mixtur Interactive, Inc. -@- http://www.mixtur.com

>
>
>On Feb 15, 2005, at 10:09 AM, Florian Lefeuvre wrote:
>
>  
>
>>> Hi all,
>>>
>>> I use a GSM device to send dtmf on my asterisk system (via SIP).
>>> the codec I use is ulaw (or a-law).
>>> dtmf mode is INBAND.
>>> relaxmode is on.
>>> but most of the case,  I 'missed' some DTMF or
>>> I 'double' one.
>>> as anybody as seen this before?
>>> is there any way to prevent this
>>>
>>    
>>
>
>I suffer from this problem all of the time but I'm configured for 
>out-of-band dtmf on the asterisk side thanks to IAX2 trunking. I think 
>the problem is GSM or maybe cell phones in general. I know this has 
>been discussed before.
>
>-mark
>
Thanks for your response mark,

I find the compilation option RADIO_RELAX.
this option change a threshold in DTMF detection (function dtmf_detect 
in dsp.c)
I remark an big improvement in the detection of the dtmf over GSM.
have you ever test this option?
RADIO is obscur for me, does it mean all wireless device?

Florian