USB-C - incorrect termination
Use a USB Type-C cable breakout board so that you can readily probe VBUS, CCx and GND. Connect a known voltage value to VBUS (because USB Type-A(m) to USB Type-C (m) cables will have their CC termination pulled up to VBUS) and a known resistor value from CC1 to GND. Use a DMM to measure the CC1 node - if your measurement is yielding the known voltage you're applying, then you've found that this CC pin is actually connected to the VCONN wire. If you measure some lower voltage value then you've discovered the actual CC wire position, and you can deduce the Rp pullup strength.