Front Runner in the Pacific side of things was running into similar issues, but without the use of TC. He plays at 1x usually, while he piddles about the house, with the game sound turned up. He was noticing a "drift" in the day / night cycle. He discovered some issues with FotRSU for us along the way, but also discovered that the game is "tied" to the old 30fps paradigm of a DirectX v9 game, and runs closest to "real" time when that is achieved. However, it was discovered that the devs apparently made it to where they expected an "average" of about 128x worth of time compression in the game, so 1x is a little slow, while 2048 is way too fast. The more TC you use, the worse it gets. Plus, high TC will mess with the audio and video stream, and introduce errors into the Save info, compounding the day / night sequence. Throw in the usual user's penchant for shelling out to Windows with the game running, and next thing you know, the sun is rising when the moon should... check-out
Base Time 2018 