We have responded to your question about listening to Internet Radio with the TV off HERE.
As far as the system not controlling your devices, there are few steps that could potentially help. Can you try re-seating the HDMI cables? Can you also check the CEC setting on your sources (Xbox, Sky and Samsung) to ensure that it is enabled? If the device was manufactured before 2010 or so it may not have update-to-date HDMI-CEC functionality (or any CEC functionality at all). If the device was purchased more recently, check the settings menu of the device to be sure HDMI-CEC control is turned on. Some manufactures have their own trademarked name for this functionality. Samsung, for example, calls this Anynet+.
Also, in the Unify setup menu, can you try removing and re-adding your devices? Doing this while connected to the internet will force the system to retrieve the latest set of remote codes for the device being connected.