Laggy and choppy rendered video

Hi, I've been using adobe after effects- and media encoder 2020 for quite some time.. These couple of months though I've experienced that the last frames turn fully white or black. Sometimes the frames are very choppy and laggy. It's just a couple of frames but it can be very annoying when you've worked on a project for a long time and when you render it, it's ugly. This only happens when I put color grading.

Another problem is that every once in a while, when I want to continue on my project ae tells me that my file has been corrupted or damaged for no reason. I can play my video normally through other apps but not in ae.