On Thursday, December 1, 2016 at 2:03:12 AM UTC-8, wrote:
I have an inexpensive pair of powered computer speakers. ...[ wilth loss of power]
I put a meter on the plug, wiggled the cord and there is no loose
connection. I opened the speaker and found that if I wiggle the male
plug socket soldered onto the circuit board, I make and break the
connection.

In brief, that male connector has a bad connection and needs to be
replaced.

No, it seems that the printed wiring board has a crack and needs repair.
Or, the solder joint to the connector that connects it to the printed wiring board
is faulty, and requires a bit of solder flux and reheating.

Get a lens out, and examine carefully.