FAX issues - Cisco ATA 112

[afenton]

Hi All,

Im currently experiencing an issue with a cisco ata 112.

Its currently registered with the sip provider and works perfectly to make calls when connected to a telephone.

the moment we have a fax connected to the line, it stops working. the fax is able to place telephone calls over the ata and the callee can pick up, however if you call the fax with an external line, the ata will drop connection and re-register with the sip provider, the fax shows as receiving. normally if we call a fax over ATA we can hear the fax signalling.

unable to send or recieve faxes, the speed has been set to 9600 on the fax

Kind regards,

Aidan

[Dan Lukes]

Log of voice application running on SPA112 (captured during the affected call) ?

Overall configuration of options affecting fax transmission ?

Codec used during the affected call ?

Capture of SIP communication between SPA112 and provider ?

[afenton]

Hi Dan,

The attached image is the settings in the audio config regarding fax that i have set. currently the syslog and debug server has been setup, i can replicate the issue and pass along the results. debug level is set at 0 does this need to be changed?

Will update ticket shortly with the Codec used in call. If i use a mobile to call the ata while the fax is attached on line 1, as soon as the call is passed to the fax, the ata drops and will need rebooting. ill get some details on this call.

Aidan

[Dan Lukes]

Which voice provider and which country ? G711u is neither most preferred codec in UK nor optimal FAX passthru codec. Follow your voice provider documentation, but I guess you should use G711a as the only codec.

Is T.38 protocol supported by the provider in question ? It's rather rare, but you have it enabled.

With log and SIP communication captured I may be able to provide more valuable advice.