Replays are faster than gameplay

I'm not even entirely sure if this is a bug, but I'm going to put it here because it feels like one. I had a feeling something was off editing a video were I was doing a basic picture-in-picture video where the gameplay is the big video and the replay is the small video in the corner. No matter what I did, the videos just start going out of sync after a certain point, usually after a couple minutes. To figure out why I lined up the frames from both videos when the stage starts and compared the times from when the car crosses the finish line. The replay was a full second faster than the actual gameplay on a almost 12 minute stage. When watching/playing, you wouldn't notice because it's a less then 1% change in speed, so its basically imperceptible, but when making a video, that change in speed is impossible to deal with if you don't notice or have a long enough replay. Is it gamebreaking? No. Does it impact gameplay? No. But it's something that can possibly be fixed.