GDS3710 - Cisco 9971 - Latency video


I bought a GrandStream GDS3710 to link with Cisco CME and Cisco 9971 phones.
Everything works fine, I just have a little issue. When I receive a call from the GDS3710, there is no video. I have to hold the call and un-hold it to have the video.

I think this is a latency about camera, but I’m not sure.

Have you got some ideas against this little issue?



When you put the call on-hold, this likely sends a new Invite as does when taking off of hold. I suspect the latter Invite is then negotiating the needed video codec. A Wireshark capture is needed to see what messaging is occurring between the devices - phone, CME & GDS.


Yes there is codec renegotiation and It start from Cisco to GDS (reverse).
So i guess Cisco do not correctly resolve initial INVITE and cannot establish video.
Compare both invites and change cisco or GDS settings.


hello jb, i am having a few problems with this video door station, when i make the call from the gransstream i cant hear anything, but when i call from cisco 8945 i can hear and talk, also i have problems with the video, could u post ur config? thanks


If all else fails and the Cisco / Grandstream mix do not work that well… Give the receptionist a second Monitor and stream the camera of the door phone to the monitor using VLC (Video Lan program)

eg if your GDS 3710 was at IP

You could use the following in VLC media player - using the OPEN STREAM function


That will open up the direct link to the GDS - replace the PASSWORD with the real password and replace the IP address of with the real IP.

The above is just a work around if you cant get the video working via the telephone…


We need tcp dump (wireshark, pcap).
AFAIR video in cisco what using not standard payload value for codec ? (101 afair) instead of 99.
Check if you can change it to 99 on Cisco.


Yes, @Marcin is right, Grandstream using default payload 99 for video and Cisco or PloyCom are using other values. If those values are not synchronized, no way video will come out, just like English talking to German.

Another work around if no video coming out, download the free GDSManager for Receptionist PC so let the receptionist see the live video stream from GDS3710 and click the open door icon to open door or click intercom button to talk to the visitor.

Thank you for using GDS3710!


I opened a ticket and we the GrandStream engineer determined the problem. It was the Payload value. They added this option to allow user to modify it in GDS3710 in an update. But Cisco use the payload value at 0 and the GDS cannot be set at 0. Others brand of Video Door System have option to set payload value at 0.
I tried to find the payload value in Cisco CME but didn’t found it.


@jb.ponce: Current the GDS3710 allow payload type range is 96~127, the dynamic range. Will check with our engineering to see whether 0 is a legal value and allow to be configured. If yes, the issue will be addressed in next firmware cycle.

Thank you for using GDS3710!


I asked him to do this like others Video Door System, but they don’t want to change and allow the value 0.


@jb.ponce: I checked with our engineering: Payload type 0 is defined as PCMU (G.711) audio. H.264 should use dynamic payload type which is between 96 - 127.

So we are doing nothing wrong here. Thanks!


It is possibly Cisco doing funky stuff again… :slight_smile:


Video is displayed with other SIP client (iPhone and Windows) but not on Cisco devices.