D-Link DVC-1100 Manual page 57

Troubleshooting (continued)
9. No video in a call.
Video cables are not plugged in correctly. Ensure that your video
cables are correctly plugged into the TV. Make sure that the TV is set for
video input. Consult your TV manual for reference.
Incorrect network speeds. See #23 Incorrect Network Speeds Section
in this Troubleshooting Guide.
VideoPhone is not functioning properly behind a firewall.
Place the IP address of the VideoPhone in the DMZ of the firewall. Consult
your router's documentation or your network administrator for help on
doing this.
Port forward the appropriate ports to the VideoPhone. The
VideoPhone needs ports 1720 (TCP) and ports 15328-15333 (TCP and
UDP) open to function properly. See the section Using the DVC-1100
with Routers, Gateways or Broadband Modems on page 50, or consult
your router's documentation or your network administrator for help on
doing this.
VideoPhone is not functioning properly behind NAT.
Go to Settings>Network>Public IP. Press Enter on the remote when
the cursor is over "Auto detect public IP Address." If the VideoPhone is
unable to detect the public IP Address, it should be entered manually
using "Use specific IP Address." The VideoPhone's public IP Address is
given to you by either your ISP or network administrator.
10. Video freezes during a call.
Other party muted their video. If the other party mutes their video
you will not be able to see him or her.
Network is congested. Give the VideoPhone a couple of minutes to try
to recover, or disconnect the call and try again at a later time.
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