Visimeet offers a few types of connections methods that can greatly affect the quality of the connection.   Open Connection Tab in Tools>Option from the Visimeet Control Panel.  The Connect Method can be found towards the bottom of the option list.  The default is Automatic.  Try the different options in turn to see if performance is improved.  The TCP 46000 method is designed to pass through firewalls with the most reliability while RTSP is best for networks with high latency such as satellite, remote locations or mobile networks.