Strange lines on test screen

An odd thing happened the other night, I was just fine tuning the point convergence on my NEC 9PG+ and I noticed that the bottom of the test grid looked like a row of S's. I was told that this may be over scanning but I am not sure how it apperaed on the test grid.

It results in a fine line at the bottom of the screen when playing a DVD. I run the signal through a quadscan pro.

Does anyone know what this is or how to remove it etc?

Thanks

 

I would try it with a disk that you know has no macrovision. Normally it would affect just the top but projectors are fickle

 

Its more of a smudge than a line, but why the squiggles on the test pattern when only the pj is on?