Fax is not accepting incomming calls

[mart3cx]

Hi,

i have 3CX V10 Sp1. The fax has an analog line and is connected with linksys spa2102 adapter to the 3cx. Outgoing faxes are working fine. But when I try to get an fax (incomming) the call is terminated after some seconds and the in the log apears . The fax machine is an adler-triumph dcc2725

...
10:09:40.333 [CM503008]: Call(128): Call is terminated
10:09:40.328 [CM503021]: Call(128): ACK is not received
10:09:38.424 Currently active calls - 1: [128]
10:09:10.747 [MS210002] C:128.1:Offer provided. Connection(transcoding mode): ....
10:09:10.746 [MS210000] C:128.2:Offer received. RTP connection: ....
....

TX
Mart

 

[leejor]

I suggest you do a search through the forum, you will find that you are not the only person to encounter fax problems. There are many factors to take into account (provider/gateway, ATA settings/make, Fax machine make), some people have overcome their issues, but, others have realized that it just will not work, in their case.

 

[KerryG]

It is generally a bad idea to try to run a fax machine through an IP PBX. You are introducing latency and adding packet handling. This is usually bad for faxing.

 

[eagle2]

I have a customer with VoIP provider not supporting T.38 faxing.

The customer has a SPA-3102 VoIP adapter (same functionality as SPA-2102) and an HP MFP fax. I have changed the default fax extension in 3CX to the extension number of the SPA-3102 FXS port, which I had created as fax extension in 3CX. This setup seems to be OK, as almost all faxes (incoming and outgoing) are passing successfully (9600 BPS max speed, ECM ON).

Otherwise, I read in the forum that if your provider is supporting T.38, the only way to receive fax is to use the system fax extension (888) for fax to e-mail. This could be an issue if your provider is using T.38 (and the statement is true).

Regards