Quote:
Perhaps it was just barely making contact and messing with the cable caused a solder joint to break?

Yup. It's a heavily stressed mechanical component, which unfortunately was installed without regard to such -- instead it simply tries to rely upon ordinary surface mount soldering on small pads. The PCB was laid out with the correct holes for mechanical fasteners, but the connectors that were used used lack them.

Every time the unit is moved from horizontal (car, desktop, or dock) to vertical (carrying by the handle), considerable mechanical stress is placed upon the flimsy IDE header connections. Ditto for each time the cable itself is unplugged or reconnected.

The normal fix is to resolder it using sufficient new solder to establish at least a hint of a mechanical bond, and then to extend the IDE cables by a few centimetres to relieve the stress from carrying the unit.

Cheers