I have a Sanyo tube TV and a Magnavox VHS/DVD RECORDER that I am trying to make work to record through a "basic" cable box that has only an HDMI connector. It's all set up, and I get a picture, but when the Source is "video" which I need it to be to record, the color blinks on and off really fast. I've tried different HDMI cables (2) and 2 RCA a/v cables to no avail. Can you tell me what I'm doing wrong? Would a better quality cable make any difference?