Copy-Protected CD's From '89 and '96?

Don Symes asks: "In ripping my CD library (MP3c -> cdparanoia -> bladeenc), I've run across a couple of CDs that, when played as MP3s, produce a white noise "fet-fet-fet-fet" at about 2 to 3 pulses a second. The CDs in question are Ani DiFranco, _Ani DiFranco_, Righteous Babe Records, 1989; and Israel Philharmonic, _60th Anniversary Gala_, RCA, 1996. Are these early examples of copy protected CDs, or an encoding artifact/settings issue?" Has anyone else found rip-proof CDs in there collection that exhibit this behavior? Has anyone successfully ripped any of the problem CDs listed, either here or in the comments (if so, what did you have to do)?