Question sharp 50bl2ka lines on screen when tv warms up

[alanc2k]

when first turned on the tv picture is perfect , after 5/10 minutes faint lines appear,disappear horizontally across the screen
i suspect the t con board , anyone agree ?

thanks
alan

 

[helpstar]

View: https/youtu.be/hT4rUkN7Xn0?t=328