delay after answering a call

[Anonymous]

Hi, we have a netvanta 7100 at our office it it seems that after the latest firmware upgrade (a4.03.00.sc.e) there is a few second delay after we answer a call (internally and externally) before we can hear the caller and they can hear us.  It happens on our IP712 phones and our 1 Polycom 501.

[Anonymous · Accepted solution]

darronb,

Thank you for posting this question to the Support Community.  This problem is typically due to double reINVITEs in particular call flows.  If that is the root problem there are two things that can help:

1 – Upgrade the NetVanta 7100 firmware to a version later than R10.3.1.  In this version the method the NetVanta 7100 uses to send calls to ring group members was altered to reduce answer delays.  This applies to any type of PSTN trunk (PRI, analog, or SIP) as well as internal calls.  Here is an excerpt from the R10.3.1 release notes detailing the change:

Call flow handling of ring group calls was improved to minimize answer delays. A call to a ring group on the NetVanta 7000 Series typically goes through a couple of reINVITEs. Depending upon whether the ring group users are (a) on the NetVanta 7000 Series unit itself or (b) on a branch office product connected to the unit, the number of reINVITEs can add up and lead to delayed audio. This feature improves user's experience by eliminating or reducing these delay cases.

2 – If the outside calls are coming in over a SIP trunk you can disable reinvites on that particular SIP trunk with the example configuration below:

!

config t

voice trunk T03

no prefer double-reinvite

!

NOTE: This assumes T03 is the SIP trunk that outside calls are coming in over. Replace T03 with the appropriate trunk number according to your specific configuration.

If you are using ring groups try #1 above.  If you are using a SIP trunk try #2 above.  If you are using both ring groups and a SIP trunk you may need to perform both steps.

Thanks,
Matt

[Anonymous]

Thank you Matt, we are using analog trunks on this system and the firmware upgrade fixed the problem.

[Anonymous]

darronb,

Thanks for the update.  Can you come back to this post and mark the correct answer and any other responses that were helpful with the applicable buttons (when you are logged in)?  That will mark this thread as containing an solution and help make it more visible to other users.

Thanks,
Matt

[Anonymous]

I went ahead and flagged this post as "Assumed Answered".  If any of the responses on this thread assisted you, please mark them as Correct or Helpful as the case may be with the applicable buttons.  This will make them visible and help other members of the community find solutions more easily.  If you still need assistance, we would be more than happy to continue working with you on this - just let us know in a reply.

Thanks,
Matt