Maybe the "hi-speed charger" cable needs a tighter fit to ensure it is safe to carry the relatively high current?

Doesn't excuse poor mounting inside the unit, though.

IIRC, USB connectors have evolved to put the springs inside the cable connectors - the original USB connectors having springs in the mainboard connectors - because cables are easy to replace when the springs get too weak. That shows how often USB connectors are normally expected to be inserted and removed.