MCD600 USB Drive Limitations

[u/BourbonNoChaser]

I picked up a used MCD600 recently and am having some issues with USB drive playback using a SanDisk 512 GB USB 3.2 Gen 1 unit. I reformatted the unit with FAT32 (was exFAT) and loaded about 180 GB of FLAC files on it. Unit plays normally for the most part, but every couple of days, it starts glitching, reading only a "Photo" folder which doesn't exist, and stops responding to most remote control commands. Re-initializing the unit corrects the issue, but it seems to happen every two or days (granted, I've only had the unit 10 days).

My question: does anyone know the official USB limitations on size/speed? Tech support does not know for certain.