ditched the composite cable and ordered a d-sub to component
i think the cables for megadrive are ok as both are new from retrocables uk.
gamecube works ok through the same euroscart cable adapter
will try the sync settings next
cheers

ok changed sync level on megadrive,got it almost playable on 15 ,flickers slightly every 4 or 5 seconds and only loses signal while playing now
i believe the euro scart with sync stripper is needed?
can get nice scanlines by pressing a button and setting -visual set>scan-a- to 25
just need to learn how to remove the coloured border now,its usually blue or purple im iright in thinking its ts a setting in visual?
there are a lot of settings like h-pos h-height and stuff like that,im not sure which ones effect picture size or scanline settings etc
i think if i could better understand these terms and how they effect the picture i could do a lot more through trial and error.
cheers