I have a 4-head Sony VCR, Sony Receiver, and Sony DVD player all hooked up to my Philips TV. For the past couple of years all devices have acted as they should. Recently, however, I have been experiencing recording problems with the VCR. Several times I have taped a show only to find that I only have sound only for the commercials! The picture is fine and the commercial audio is fine. Do you have any ideas or suggestions as to what the problem is?