Playback speed too fast

I was editing a video and everything was working perfectly until the next day, when I started a new project. In the new project, the playback speed was too fast, making the audio choppy and unbearable to listen to. I experted the project, and the speed was fine there. I tried using Shift+J and Shift+L to change the playback speed, but it got to the point where it was either slightly too fast, or slightly too slow. Either way, the audio was choppy. Then, when I went back to the video I had been editing the day before, that video had the same problem. I even opened a project file that I hadn't worked on since January, and it had the same issue. I tried reseting my preferences but there was no change. I also tried reinstalling Premiere Pro.

I don't know why this happened, but I can't edit effectively because of it. Any help is appreciated.