Philips Projection TV dark horizontal lines on picture

A Philips 43PP7445/69 Projection TV came in for repair with complaints of black horizontal lines on the picture. At first it seems that an interference in the video circuits is causing the problem. But when I entered the convergence alignment mode the problem showed itself as horizontal jittering which can be seen in the vertical lines of the convergence alignment cross.

By swapping boards the problem was isolated to the ACS Panel which controls the convergence alignments.