[Freeswitch-users] fax goes out at 9600 but not at 14400

[Steve Underwood]

On 03/27/2013 12:34 PM, Luis Daniel Lucio Quiroz wrote:
> Steve,  from my side there is not ATA plugged.
>
> can you suggest me a workarround?
Workaround? There is no magic solution for a broken path. What is the 
path between your FS box and the FAX machine? It can't be a low bit rate 
codec problem, as they breaks all modems. A G.726 link in the path could 
explain it. That codec works for V.29 pretty well, but V.17 won't get 
through it. The problem usually turns out to be a low quality 
analogue-to-digital interface somewhere in the path.

Steve
>
> 2013/3/26 Steve Underwood <steveu at coppice.org>:
>> Hi,
>>
>> The commonest reason for 14,400 failing and 9600 working is the call is
>> going out through a poor quality ATA. A *lot* of ATAs seem to badly
>> degrade the analogue signal. If it were a digital domain issue, like
>> packet loss or a jitter buffer messing up the timing of the signal, this
>> should affect 9600 just as much as 14,400.
>>
>> Regards,
>> Steve
>>
>> On 03/27/2013 07:22 AM, Luis Daniel Lucio Quiroz wrote:
>>> Hello
>>>
>>> Look
>>>
>>> 2013-03-26 19:12:42.602751 [DEBUG] mod_spandsp_fax.c:487
>>> ==============================================================================
>>> 2013-03-26 19:12:42.602751 [DEBUG] mod_spandsp_fax.c:500 Fax
>>> processing not successful - result (49) The call dropped prematurely.
>>> 2013-03-26 19:12:42.602751 [DEBUG] mod_spandsp_fax.c:505 Remote station id:
>>> 2013-03-26 19:12:42.602751 [DEBUG] mod_spandsp_fax.c:506 Local station
>>> id:  SpanDSP Fax Ident
>>> 2013-03-26 19:12:42.602751 [DEBUG] mod_spandsp_fax.c:507 Pages transferred: 0
>>> 2013-03-26 19:12:42.602751 [DEBUG] mod_spandsp_fax.c:509 Total fax pages:   0
>>> 2013-03-26 19:12:42.602751 [DEBUG] mod_spandsp_fax.c:510 Image resolution:  0x0
>>> 2013-03-26 19:12:42.602751 [DEBUG] mod_spandsp_fax.c:511 Transfer
>>> Rate:     14400
>>> 2013-03-26 19:12:42.602751 [DEBUG] mod_spandsp_fax.c:513 ECM status         off
>>> 2013-03-26 19:12:42.602751 [DEBUG] mod_spandsp_fax.c:514 remote country:
>>> 2013-03-26 19:12:42.602751 [DEBUG] mod_spandsp_fax.c:515 remote vendor:
>>> 2013-03-26 19:12:42.602751 [DEBUG] mod_spandsp_fax.c:516 remote model:
>>> 2013-03-26 19:12:42.602751 [DEBUG] mod_spandsp_fax.c:518
>>> ==============================================================================
>>>
>>> Bug if transfer rate is 9600 it goes for good.
>>>
>>> Currently Im passing these variables, but seems it is not working.
>>>
>>>
>>> 2013-03-26 19:12:08.632735 [DEBUG] switch_ivr_originate.c:2005 Parsing
>>> global variables
>>> 2013-03-26 19:12:08.632735 [DEBUG] switch_event.c:1569 Parsing
>>> variable [disable-v17]=[true]
>>> 2013-03-26 19:12:08.632735 [DEBUG] switch_event.c:1569 Parsing
>>> variable [fax_v17_disabled]=[true]
>>> 2013-03-26 19:12:08.632735 [DEBUG] switch_event.c:1569 Parsing
>>> variable [fax_disable_v17]=[true]
>>> 2013-03-26 19:12:08.632735 [DEBUG] switch_event.c:1569 Parsing
>>> variable [fax_transfer_rate]=[9600]
>>> 2013-03-26 19:12:08.632735 [DEBUG] switch_event.c:1569 Parsing
>>> variable [ignore_early_media]=[true]
>>> 2013-03-26 19:12:08.632735 [DEBUG] switch_event.c:1569 Parsing
>>> variable [absolute_codec_string]=[PCMU]
>>> 2013-03-26 19:12:08.632735 [DEBUG] switch_event.c:1569 Parsing
>>> variable [origination_caller_id_name]=[anonymous]
>>> 2013-03-26 19:12:08.632735 [DEBUG] switch_event.c:1569 Parsing
>>> variable [origination_caller_id_number]=[16138007358]
>>> 2013-03-26 19:12:08.632735 [DEBUG] switch_event.c:1569 Parsing
>>> variable [fax_enable_t38]=[false]
>>> 2013-03-26 19:12:08.632735 [DEBUG] switch_event.c:1569 Parsing
>>> variable [fax_retry_attempts]=[32]
>>> 2013-03-26 19:12:08.632735 [DEBUG] switch_event.c:1569 Parsing
>>> variable [fax_retry_limit]=[32]
>>> 2013-03-26 19:12:08.632735 [DEBUG] switch_event.c:1569 Parsing
>>> variable [fax_retry_sleep]=[180]
>>> 2013-03-26 19:12:08.632735 [DEBUG] switch_event.c:1569 Parsing
>>> variable [fax_verbose]=[true]
>>> 2013-03-26 19:12:08.632735 [DEBUG] switch_event.c:1569 Parsing
>>> variable [fax_use_ecm]=[off]
>>> 2013-03-26 19:12:08.632735 [DEBUG] switch_event.c:1569 Parsing
>>> variable [fax_enable_t38_request]=[false]
>>> 2013-03-26 19:12:08.632735 [DEBUG] switch_event.c:1569 Parsing
>>> variable [execute_on_fax_success]=[system
>>> /usr/local/bin/email2fax.unqueue
>>> /var/spool/push.fax/1981467.bl4Q53kE2n at everardo.okay.com.mx
>>> test.pdf.tiff.to.16136997792 at faxofaxo.com.job]
>>>
>>>
>>> Does anyone have an idea?
>>>
>>> LD
>>>