Faxes sending twice

Hi folks, long time lurker, first time poster.

I’ve been sending faxes with moderate success for a while and have hit upon a puzzling problem after changing VoIP providers. I’m using a web fax portal created by CSRDU (web page now non-existent). It generates a call file that is put in /var/spool/asterisk/outgoing to initiate the fax call. That call file remains in the spool until the call completes. The problem I’m experiencing is that asterisk is executing the call file again while the fax is in progress. I’d seen this happening before but it wasn’t a big deal because the line was busy. But since changing providers I’m discovering that two calls are now being allowed to go out simultaneously. And a lot of the businesses I fax seem to have capability for multiple incoming faxes on the same number. So end result is I keep spamming my recipients with two of the same fax. Is there something I can do in my dial plan to prevent more than one call at a time on that line? Or some way to stop asterisk executing the call file a second time?

You’d need to provide the actual console output and contents of the call file. The behavior is that a call file won’t do another call at the same time, so it’s likely something else occurring as a result.

Thanks. I’ll try to collate these next time I send a fax. Should I turn on any extra fax/sip debugging for the console output or just use what it shows when I use the -rvvv flags?

SIP level isn’t really needed, as that is not what would be controlling multiple calls.