Basically i've had this issue since i reinstalled my windows 10 about 2 months ago.
It's very annoying cause i need about few days to edit simple 10 minute video with all these lags, when if it wouldn't lag i could do it in a hour.
I've uploaded a youtube video to make things clear what exactly is my issue. I've tried 90% of fixes i've found in internet, none helped;
Might be my PC issue, but as far as i know it should be more than enough for simple editing like this
PC SPECS :
FX-6300 @ stock 3.5
8gb crucial ddr3 ram
GTX 750ti