[asterisk-users] Duplicated DTMF with bridged IAX channels maybe?

[James Lamanna]

On Wed, Apr 28, 2010 at 6:57 PM, James Lamanna <jlamanna at gmail.com> wrote:
> Hi,
> I have a duplicated DTMF issue with, it appears, bridged IAX channels.
> I have the following setup:
>
>   PRI                  IAX
> <-------->* PSTN <------->* Dialplan
>
> I've configured a number on the dialplan server to make and outbound
> call to the pstn. This call then comes back into the dialplan server
> to SayDigits().
> I'm seeing that a few of my digits are being duplicated every so often.
> I've attached an IAX trace from the PSTN server to this message where
> you can see the duplication (digits 9 & 3). The digits entered were
> 258963.

[snip]

Testing the following scenario:
Call --(from pstn PRI)--> (PSTN box) --IAX--> (PBX box) --IAX--> (PSTN
box) --(to/from pstn PRI)--> (PSTN box)
Results in Duplication.
Here are 2 traces from the PSTN box's DTMF log:
'8' was not duplicated, '9' was.
Zap/42-1 is the first inbound leg from the PSTN
IAX2/w2bpstn-8399 is the leg from the PBX box to the PSTN box
Zap/53-1 is the inbound leg from the PSTN

[Apr 29 17:02:15] DTMF[16062] channel.c: DTMF begin '8' received on Zap/42-1
[Apr 29 17:02:15] DTMF[16062] channel.c: DTMF begin passthrough '8' on Zap/42-1
[Apr 29 17:02:15] DTMF[16065] channel.c: DTMF begin '8' received on
IAX2/w2bpstn-8399
[Apr 29 17:02:15] DTMF[16065] channel.c: DTMF begin passthrough '8' on
IAX2/w2bpstn-8399
[Apr 29 17:02:15] DTMF[16071] channel.c: DTMF begin '8' received on Zap/53-1
[Apr 29 17:02:15] DTMF[16071] channel.c: DTMF begin ignored '8' on Zap/53-1
[Apr 29 17:02:16] DTMF[16062] channel.c: DTMF end '8' received on
Zap/42-1, duration 63 ms
[Apr 29 17:02:16] DTMF[16062] channel.c: DTMF end accepted with begin
'8' on Zap/42-1
[Apr 29 17:02:16] DTMF[16062] channel.c: DTMF end '8' has duration 63
but want minimum 80, emulating on Zap/42-1
[Apr 29 17:02:16] DTMF[16062] channel.c: DTMF end emulation of '8'
queued on Zap/42-1
[Apr 29 17:02:16] DTMF[16065] channel.c: DTMF end '8' received on
IAX2/w2bpstn-8399, duration 0 ms
[Apr 29 17:02:16] DTMF[16065] channel.c: DTMF end accepted with begin
'8' on IAX2/w2bpstn-8399
[Apr 29 17:02:16] DTMF[16065] channel.c: DTMF end passthrough '8' on
IAX2/w2bpstn-8399
[Apr 29 17:02:16] DTMF[16071] channel.c: DTMF end '8' received on
Zap/53-1, duration 223 ms
[Apr 29 17:02:16] DTMF[16071] channel.c: DTMF end passthrough '8' on Zap/53-1

[Apr 29 17:02:16] DTMF[16062] channel.c: DTMF begin '9' received on Zap/42-1
[Apr 29 17:02:16] DTMF[16062] channel.c: DTMF begin passthrough '9' on Zap/42-1
[Apr 29 17:02:16] DTMF[16065] channel.c: DTMF begin '9' received on
IAX2/w2bpstn-8399
[Apr 29 17:02:16] DTMF[16065] channel.c: DTMF begin passthrough '9' on
IAX2/w2bpstn-8399
[Apr 29 17:02:16] DTMF[16071] channel.c: DTMF begin '9' received on Zap/53-1
[Apr 29 17:02:16] DTMF[16071] channel.c: DTMF begin ignored '9' on Zap/53-1
[Apr 29 17:02:16] DTMF[16071] channel.c: DTMF end '9' received on
Zap/53-1, duration 223 ms
[Apr 29 17:02:16] DTMF[16071] channel.c: DTMF end passthrough '9' on Zap/53-1
[Apr 29 17:02:16] DTMF[16071] channel.c: DTMF begin '9' received on Zap/53-1
[Apr 29 17:02:16] DTMF[16071] channel.c: DTMF begin ignored '9' on Zap/53-1
[Apr 29 17:02:16] DTMF[16062] channel.c: DTMF end '9' received on
Zap/42-1, duration 63 ms
[Apr 29 17:02:16] DTMF[16062] channel.c: DTMF end accepted with begin
'9' on Zap/42-1
[Apr 29 17:02:16] DTMF[16062] channel.c: DTMF end '9' has duration 63
but want minimum 80, emulating on Zap/42-1
[Apr 29 17:02:16] DTMF[16062] channel.c: DTMF end emulation of '9'
queued on Zap/42-1
[Apr 29 17:02:16] DTMF[16065] channel.c: DTMF end '9' received on
IAX2/w2bpstn-8399, duration 0 ms
[Apr 29 17:02:16] DTMF[16065] channel.c: DTMF end accepted with begin
'9' on IAX2/w2bpstn-8399
[Apr 29 17:02:16] DTMF[16065] channel.c: DTMF end passthrough '9' on
IAX2/w2bpstn-8399
[Apr 29 17:02:17] DTMF[16071] channel.c: DTMF end '9' received on
Zap/53-1, duration 223 ms
[Apr 29 17:02:17] DTMF[16071] channel.c: DTMF end passthrough '9' on Zap/53-1

-- James