Campagnolo rear brake movement

The good doctor

If I squeeze the two brake pivots together and let go they both return to their original postition however when using the brake lever only one returns to its posiiton. I can also move both pivot arms from left to right but the whole brake assembly is securely fixed to the frame.
Can anyone tell me what needs adjusting please, the pivot arm staying put is I imagine, a cable issue but not so sure about the other problem.

Thanks
John

Monty Dog

Have you tried adjusting the tension screw on the brake arm? It's a small grub-screw needing a 2.5mm or so Allen key.

The good doctor

All fixed thanks

John