Intermittent disconnects when leaving a message on a remote answering machine.

[Inder38]

Hi Folks,

I have an IP Office 500V2 7.0.(31) which is using SIP trunking to a local ITSP. There is one user who is making a lot of outbound calls and every now and then when attempting to leave a voicemail, the message tone from the far end will trigger a tone and then a disconnect on the IP office side. This is only happening intermittently and is the only issue reported by this customer.

Has anyone seen anything like this in the past? Numerous searches have not given any results.

Thanks
Craig

 

[janni78]

Do a monitor trace to which end send the BYE.

"Trying is the first step to failure..." - Homer

 

[Inder38]

I've looked at the entire SIP conversation between the IPO and the ITSP, and it is the IPO transmitting the BYE. I have since been able to duplicate this, and when I start to leave a message on the far end voicemail, after 2 or 3 seconds the IPO gives two audible beeps and disconnects the call.

At the same time in the monitor trace, the ITSP is sending an UPDATE packet, when causes the IPO to try to re-establish the call.

 

[janni78]

I would probably try to upgrade the PBX since SIP has evolved a bit since 7.0 in IPO.

Don't know if it's available in 7.0 but you could try to change the "Method for Session Refresh" to REINVITE if the UPDATE is the issue.

"Trying is the first step to failure..." - Homer