The jack on the Stratocaster was causing the shorting problem. I can only surmise that my favorite Monster cable spread the contacts over the years, and basically wore out the jack. At any rate, after a whirlwind trip to Guitar Center and some quick soldering, the guitar is working perfectly with all my standard cords. The Monster cable has been relegated to the gig bag as a spare. It was a great cable, but I’m not sure I want to continue using cables that actually wear out my equipment.