Hi

I have an amplifier with RGB and Sync Phono connectors and I am
connecting this to a scart equipped TV. (Input from source DVD player
goes to to the AVAMP and then routed to TV from the AMP). I am
receiving an image on the TV when I select the scart to be in RGB mode
but there are some flickering lines on the screen. This is not the
whole image flickering (as happens if I disconnect the sync cable) it
is multiple (single pixel) flickering lines going horizontally across
the screen.

I have independently disconnected each RGB cable (obviously this
changes the colour of the image) to see if it is either of these cables
but the lines remain. If I disconnect the sync cable the image is
completely unstable as would be expected and therefore I cannot tell if
the lines remain.

If I connect SCART to SCART from DVD to TV in RGB mode then the image
is fine.

If I connect SCART to S-video (DVD to AMP) and s-video to SCART (AMP to
TV) image is fine.

If I connect SCART to S-video (DVD to AMP) and RGB+Sync (Phono) to
Scart) (Amp to TV) - AMP does conversion from s-video to RGB - I get
the flickering lines.

Does anybody have any idea what may be the cause of these flickering
lines or at least how I might diagnose them. Could it be bad shielding
on the cable, a missing pin connect, bad grounding?

Thanks in advance.