Random 403 Forbidden with CBeyond

[technology7]

Once or twice a day I am getting 403 forbidden for a couple of minutes, then it clears. According to CBeyond 3CX is sending an invite with the user's name instead of the extension. This is weird because it works most of the time. The message they have sighted looks like this: From: "773754xxxx"<sip:[email protected]:5060>;tag=0c408f41 (the xxxx replaces the number for security reasons but the number is the BTN). They say the "Carri" should be the extension.
Support has had me change a couple of the outgoing parameters, without effect. It seems to me that if those were wrong I would not be able to make calls at all. Any ideas? 3CX 10 SP2.

 

[technology7]

No word from the community but here's my update.
I have been tossed back and forth by 3CX and CBeyond. 3CX has washed their hands of this and CBeyond continues to provide non-fixes. I have probably put in 6 or 7 changes and nothing makes any difference. At this point I am moving my client to Broadvox, part as a test, part as a remedy. I expect the problem to go away as I use Broadvox without problems. This is very disappointing as 3CX is supposed to be certified with CBeyond but I guess that means nothing. I've no doubt I can continue talking to CBeyond until the cows come home and they will continue to offer non-solutions, but frankly I don't have time. Buyer beware of this combination, unless you are a SIP expert or have weeks to waste.

 

[garyjduk]

I've had the same intermittent Forbidden message from a Spitfire SDSL line and SIP trunk.

After being assigned a SIP engineer to monitor the line we have worked out that due to interference sometimes the SIP platform doesn't get the BYE message at the end of a call and the SIP trunk remains open. We have 8 SIP trunks and on bad days sometimes no one is on any lines but all SIP trunks remain open. Sometimes Spitfire have to manually reset the trunks to make them available. We are in the process of moving to a new platform to try and fix this and BT are examining the line.

You'd think being in London Mayfair on the Mayfair exchange across the other side of the square would be a good connection but the line length is about 1km! Not sure where it's routed via?

Anyway sounds the same kind of problem and it's coming from the SIP provider rather than 3CX.