4211. Video freezes during a call.Far side muted their video. If the far side mutes their video youwill not be able to see him or her.Network is congested. Give the VideoPhone a couple ofminutes to try to recover, or disconnect the call and try again at alater time.12. No audio in call.Audio cables are not plugged in correctly. Ensure that youraudio cables are correctly plugged into the TV. Make sure that theTV is set for video input. Check the volume level on the TV.Consult your TV manual for reference.Telephone is not set-up properly. Plug the telephone into theback of the VideoPhone. If the telephone is powered (cordless)make sure that it is plugged into a power supply. Consult yourtelephone user manual for reference.VideoPhone is not functioning properly behind a firewall.Place the IP Address of the VideoPhone in the DMZ of thefirewall. Consult your routerís documentation or your networkadministrator for help on doing this.Port forward the appropriate ports to the VideoPhone. TheVideoPhone needs ports 1720 (TCP) and ports 15328-15333(TCP and UDP) open to function properly. Consult your routerísdocumentation or your network administrator for help on doingthis.Troubleshooting (continued)