The firmware was modified to report a larger size (e.g., 2TB) than the physical NAND (e.g., 32GB), leading to write errors and heat.
The is a classic case of "you get what you pay for." The new "hot" firmware makes it usable, but it will never be reliable. Use the updated MP tool, set aggressive thermal limits, and never store your only copy of a file on one. firstchip fc1178bc firmware hot