Sony 32" screen flashing on and off

i just fix my tv last day was flashing on off on every chanel i simply open the back cover (case) and beside the power unit on the left side bottom have about 2 inches high a black box with 2 think like a screw you can turn them there in plastic with a flat screwdriver the bottom one is the one you turn litle bit direction of the clock i symply remove back and plug the tv on turn that tink and my screen never blink anymore (sory for error writing iam french)

Try turning up screen control on flyback ontil you see retrace lines on screen and then back off ontil they just dissapear mite help it for awhile.

if the problem is on and off, probably there are some cold solder joints. If you have electronics knowledge, check out the board behind the CRT and components (and solder joints) around the HOT and Flyback transformer. Maybe you will see something loosen