How legal is Displaying paid third party advertisements

We are developing a device which can be attached any TV to display advertisement in the TV. This device can be used by shops/restaurants/bars/hospitals to display advertisements in their premises. We also have a platform which is used collect third party advts and display it in those TVS if the TV host is ready for displaying third party advertisements. TV Hosts will be paid by our platform for displaying third party advertisements. We also provide a facility in this device to accept an input to connect a set-top box/DVD player/any video source. The video from this input will be used a filler in between advt. We would like to know whether this will attract any legal objection from government/cable TV operators etc.