I have been using Grandstream Wave at work or home with no problem with Wifi. However, it’s not working when I use it with cellular network. I can make calls. But video/audio can’t go through. My service provider is T-Mobile, which assign ipv6 address to my cell phone.
I did a packet capture and compared the working and non-working calls. In the non working scenario (IPv6 address), Grandstream Wave sends RTP traffic with different source port than the media port specified in the INVITE packet. But the source port of the RTP packet matches the media port in the INVITE packet in the working scenario (IPv4).
Is there any configuration setting I need to change to make it works? The manual indicates IPv6 is supported.