Whenever I receive this warning, telling me to open ports 5558 and 5556, what I do instead is:

netstat -nlupt | grep 5556

tcp 0 0 192.168.0.28:5556 0.0.0.0:* LISTEN 19790/libpepflashpl
tcp 0 0 127.0.0.1:5556 0.0.0.0:* LISTEN 24380/chrome --prof

kill -9 19790

[Restart Videostream]

Probably, something was not shutdown properly.
So Videostream cannot open a new process listening on the same port.