[Mohamed Magdy]

I used to get stuck with this problem. I finally solved it by changing the “video playback settings” from “the sequence settings” in the “sequence” menu. The default resolution is 1920 x 1080. I changed it to 640 x 360, and after that playback was always 100% smooth, even while using a mixture of .mts and .mvi full HD files, with contrast and brightness effects on them, without even having to render at all, even while the bar is red.