[jitsi-users] jitsi meet does not show remote users video input/audio input


i just wanted to give jitsi meet a try -out of the box- but the remote
video-/audio does not show up. keyboard chat is ok.
we feel, it does not make a difference if jvb is running or not.

maybe it's important to mention, that all of our machines are placed
behind a firewall and do not have direct (no natting) internet accesss -
all internet access is done via an authenticating proxy (squid-3.5.7).

what could i do to make jits meet work?

Debian GNU/Linux 8
java version "1.7.0_79"
OpenJDK Runtime Environment (IcedTea 2.5.6) (7u79-2.5.6-1~deb8u1)
OpenJDK 64-Bit Server VM (build 24.79-b02, mixed mode)

ii jicofo 1.0-143-1
amd64 JItsi Meet COnference FOcus
ii jitsi-meet 1.0.683-1
all WebRTC JavaScript video conferences
ii jitsi-meet-prosody 1.0.683-1
all Prosody configuration for Jitsi Meet
ii jitsi-videobridge 521-1
amd64 WebRTC compatible Selective Forwarding Unit (SFU)

client1: windows/firefox-41.0

client2: Debian GNU/Linux 8/Chromium-45.0.2454.85