Assuming it's nothing to do with the car, i.e. it's not new, then check the vaccum hoses, they split, introducing an air leak.

Re the unlocking, it's a common problem that cars suffer, it sounds as if one of the "Masters is sticky", i.e. the driver or passenger door, when the C/L pulse times out, one of the motor is "Stuck in the middle" and so it simply reverts.

The remedy is to lubricate both locks.

Martin