Go to your local apple store, there are several types of cables and the wrong one will not work. Check if you have a reverb unit in the system that would give that effect. It cold be picking up a speaker but normally that causes feedback with a howling sound.
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Go to your local apple store, there are several types of cables and the wrong one will not work. Check if you have a reverb unit in the system that would give that effect. It cold be picking up a speaker but normally that causes feedback with a howling sound.