I have a 721 and what I do is unplug the power cord, push the power button and hold it for a few seconds, plug the power cord into the outlet and turn the receiver on. When you turn it back on you may have to wait 4 minutes before things start to happen. You may have to do this several times but usually once is enough. If this does not correct the problem you may have to have the unit replaced. Do not expect help from Tech Support because they have no idea on how to correct 721 problems. I am an installer and have learned this from experience.gnm313 said: