[Asterisk-Users] [DTMF] Audio-Before-Answer issues

[Stefano Finetti]

Hello,

I did this post a long time ago but never solved the problem, so i'm trying
again after something like 10 months, hopefully i'll find someone that found
a solution ;-)

When i call an external number that sends audio before call has been
answered (like some PBX of public offices do here in italy), strange things
happen:

I'm using chan_capi, with Early B3 active, i can listen to the voice before
the answer, but i'm not able to send any DTMF tone.

This is the log from * console:

May 12 12:34:47 NOTICE[1142106560]: chan_sip.c:6288 handle_request: Unknown
SIP command 'PUBLISH' from '192.168.251.84'
    -- Executing SetCallerID("SIP/stefanof-194a", "199797930") in new stack
    -- Executing SetMusicOnHold("SIP/stefanof-194a", "default") in new stack
    -- Executing Dial("SIP/stefanof-194a", "CAPI/0:b803121||") in new stack
    -- creating pipe for PLCI=-1
       > sent CONNECT_REQ MN =0xc
    -- Called 0:b803121
    -- CAPI[contr1/0]/2 is making progress passing it to SIP/stefanof-194a
       > sent CALLEDPARTYNUMBER INFO digit = 3 (PLCI=0x101)
    -- CAPI Hangingup
       > sent DISCONNECT_B3_REQ NCCI=0x10101
       > sent DISCONNECT_REQ PLCI=0x101
    -- removed pipe for PLCI = 0x101
  == Spawn extension (outgoing, 803121, 3) exited non-zero on
'SIP/stefanof-194a'


You can easily find that there is obviously NO ANSWER to the call, nor
RINGING advice.
When I, hearing voice from external PBX, try to send the DTMF tone for my
choice, the dtmf seems to be sent in this way:

> sent CALLEDPARTYNUMBER INFO digit = 3 (PLCI=0x101)

But nothing happens.
(BTW, the number called is the toll-free Telecom Italia number for technical
help)

For this test i use a Snom105 Sip Phone.

Any other DMTF issues seems to have been solved, since now, if the external
PBX actually answers the line, i can send all the DTMFs tones i want and
they work.

I have also tried playing with che SendDTMF Application and using the new
cvs feature about the D([digits]) option to the Dial string. Both works only
after the answer (the latter after answer and before bridging if I have well
understood).

I'm using CVS-HEAD-05/10/04-14:56:11 with latest zaptel and libpri archives
and the latest chan_capi source (honestly i don't think it's a capi related
problem since i had the same problem also with Zap and Modem[i4l] channels.

Regards,
-- 
Stefano Finetti
Technical Coordinator
Lynx Autodelta S.r.l.