LLN make the video slower

I try to search this problem on the Internet, but seems no one have this problem. If I open LLN, it loads, but the video will be played at like 0.9x or 0.8x, you can feel it because the sounds has become slower.
May I ask anyone has this problem? Or how to fixed it?

LLN has speed controls. Open the settings and make sure the speed is set correctly.