Ran into an apparently-corrupt file and it threw a "Frame substitution recursion attempt aborting after multiple attempts on file: [path]." Program kept running, was able to remove corrupt file from bin but playback stayed broken.
Closed and restarted Premier, playback OK.
System info
Application: Premiere Pro (Beta) v24.3.0.5
OS: Windows v10.0.22621, RAM: 63.83 GB GB, CPUs (logical): 16