Temviewer 8 closes connection after 1 minute

I have just re-installed TV8 on my wife's new laptop. With old laptop I could stay on for 1hr  before TV8 closed the connection. Icould re-connect straight away if I wanted to. Why is it now closing after 1 minute & then not allowing me to re-connect until 14 min. later. I am using the free version since not being used commercially.

Regards, Allan Haddow