I am trying to set a timer recording and keep getting told that I need to set a source. The only option in these that fits our set up is Channel 3, when this is set we get a good signal and if we just hit record for the VCR or DVD it records just fine. Yet when we try to set a timer for either one when the time comes up it will not record and says that there is no signal from the set source. Please help, there is a lot of things we would like to record when we are not home.