Hi all, We’re preparing to upgrade our fs server for ipv6 supporting, but it is not going well on test. The test proceeded on FreeSWITCH 1.10.6 and LinphoneSDK 4.5.0, under IPv6Only networks. As the result, the callee couldn’t hear any voice from caller, while caller works fine. The tcpdump showed that freeswitch didn’t send any rtp packages to callee, like this: [2001::14] is FreeSWITCH, [240d::68ae] is the caller, and [240d::b342] is the callee, which missed the rtp stream from server. We tried to exchange the device of caller and callee, but result didn’t change (callee couldn’t hear any voice from caller). FreeSWITCH Console also showed no error and RTP port is set correctly. Environment: FreeSWITCH Version 1.10.6-release+git~20210325T131609Z~1ff9d0a60e~64bit (git 1ff9d0a 2021-03-25 13:16:09Z 64bit) Linphone iOS 4.4.0 with Linphone SDK 4.5.0 / iOS 13.7 Any suggestion would be appreciated. Regards. —————————————————— 王聡 cong.wang.itsherpa@gmail.com 〒810−0073 福岡市中央区舞鶴2-3-6 赤坂プライムビル 2F 株式会社アイティーシェルパ