So, a customer sent me a board with the query "whuzzup?"
It turns out that there's a resistor in there, which I mostly put in so that I could monitor current, but I kinda put in as a last-ditch fuse (1.5 ohm 0603).
On this board, the resistor is open-circuit with no discernible burning. Is there some electronic mechanism that could cause this? Or am I just looking at a faulty part?