Locate the speaker cable. Use your fingers to pinch each side of the black head of the speaker cable, and gently pull it out of its socket.

The metal spudger shown in the photo is used only to identify the speaker cable, not remove it.

If you're unable to get a good grip on the black connector head itself, gently pull from the wires near the connector head's base.

Be sure to pull on the wires near the base and evenly on the full width of the wires so no individual wire is over-strained, which may cause damage!