Inspired by gridleak's sacrifice, I also lugged down my troubled demo unit, which still has the original heads.
Using composite inputs to my monitor the unit worked perfectly on a VHS tape.The program button on the remote worked perfectly.
I am somewhat confused about your mentioning the Channel 3/4 switch. That comes into play if you are using an rf input to your TV, not the composite connections.
It is noteworthy that this unit neither plays nor records properly on D-VHS.
I do believe that using an HD1000 for VHS tapes is like using a Lamborgini to lug lumber back to the house from Home Depot.I definitely would not recommend playing rental VHS tapes, of unknown history, on it.