I can cast/mirror sky on tv with the Sky Ticket App. When I want to use the Sky Go App that doesn't work because there is not mirroring button or anything like in the Sky Ticket app. When I use the google cast function and start the sky go app it says that this is not allowed and I should use the build-in cast function (that apparently doesn't exist ?!?!). So how can I cast it with the Sky Go app???