A magnetized head can cause a slight loss of high-frequency response in the sound. We don't even talk about that anymore because it doesn't cause a problem. You need something to create a magnetic field for the heads to become magnetized. Most commonly that was a soldering iron.
Your cassette mechanism has a mechanical problem. It could be due to broken tooth on a gear, a slipping belt, or even a failed optical sensor for the auto-reversing circuit.
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Thursday, June 4th, 2015 AT 6:50 PM