2 source video/audio switcher

[rone]

Customer wants to be able to auto switch two sources of video in his waiting room. One source will be SD/HD television from the local cable televison company. The other source will be from video we produce (product demos). The idea is to have the cable signal (TV) interupted for a 30 to 60 second spot, then switch back to the cable signal for xx minutes then back to a second or third, or fourth spot, then back to the normal TV programing. This switching will take place all day and of course function automatically.

Ideas