[Freeswitch-users] DTMF problems

[Boris Kovalenko]

Hello!

Hmm... we are talking about calls coming from PRI so (AFAIK) DTMF is 
always in-band, isn't? And Cisco is responsible to detect it and send 
out-of-band. IMHO bad call quality (e.g. call from GSM) is a good 
explanation.
> No problem Boris. I never had much success with in-band DTMF but as M.
> Collins suggested in a separate thread there are some cases where you
> really need in-band detection (i.e. calls via GSM networks always send
> in-band DTMF), I suggest you try recording the calls and try to make sense
> of how much of the DTMF tone is being received, if there is stuttering due
> to echo cancellation or static on the line, etc...
>
> On Tue, 24 May 2011 16:57:15 +0300, Boris Kovalenko<boris at tagnet.ru>
> wrote:
>
>> Hello!
>>
>>       Thank You Kerem, I'll try. The main problem is that there is a
>> little percent of wrong DTMF and a very nervous customer.
>> Also what if not to use dtmf-relay on Cisco at all? What kind of
>> problems may I have? I use G711alaw inside a network. Some transit calls
>> (ie Internet ->  PSTN) may use G729.
>>
>>> Yes Boris, try setting it lower incrementally and see if it helps. There
>>> might be problems related to gain + echo on the line that confuses DTMF
>>> detection, so check if the line has echo as well. Also sometimes I have
>>> seen that the remote calling party has a POTS line with too much static
>>> it
>>> can confuse DTMF detection. On other VoIP systems we solved this problem
>>> by spying on the channel e.g.
>>> http://wiki.freeswitch.org/wiki/Misc._Dialplan_Tools_eavesdrop can be
>>> helpful in debugging the situation.
>>>
>>> On Tue, 24 May 2011 16:10:03 +0300, Boris Kovalenko<boris at tagnet.ru>
>>> wrote:
>>>
> <snip>
>>> <snip>
> <snip>
>>>
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>>
>
>
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