Debugging:Open or Short Circuit

I know that this is trivial question ,How do you find whether a circuit is open or short circuited.I have a broken headphone and when I try to find the problem using a continuity test.I have attached my circuit below.Now my question is how to find whether the circuit is open circuited or Short Circuited using a multimeter.
If the circuit is complete,I get a small sound on the speakers.
Thanks in advance.

modify the circuit that gives AC audio signal and repeat the exercise.
May be a broken small toy piono will sufiicient the requirement. Break the speaker or audio crystal unit connection. Attach leads to both ends of this broken connection to test open or short.
Ensure that the toy key is in pressed mode in default. if you connect the leads it should buzz.

Regards,
Palla

No I want to specifically know how to identify this problem using multimeter.Any help in this direction would be much appreciated.

To know whether the device you are testing is shorted, you need to be sure no other device is in parallel.
You need to be sure current is not able to go back through the wiring to another component.

To know whether a device is open, you need to be sure its terminals are connected to power (either from a supply or from your ohmmeter).
If there is an intervening component, and it is open, then you are not testing the device you think you are testing.

Sometimes you have no choice but to disassemble the headphones, and test each cable and transducer individually.

Be careful when hooking up an ohmmeter to earphones. It sends 1.5 or 9V out through its leads. This is likely to produce loud crackling noises, at a volume which depends on the amount of current available from the meter. The diaphragm may move violently, which can break connecting wires, or hasten the process.

Thanks a lot,Brad