I recently bought a new RCA DVD player ... HDMI, upconvert, etc., and I have an old school TV set with only a coax connect. So I bought an RF modulator to connect. Some DVDs work just fine, but the majority skip. I lose sound and picture, the disk advances and then picks up again. This happens throughout the entire DVD....I actually endured it once. It will go one or two minutes before it stops instantaneously...this lasts for anywhere from ca.