Ford Mustang Owner's Manual page 34

If a tape is loose inside the cassette, tighten it
before playing by putting your finger or a
pencil into one of the holes and turning the
hub until the tape is tight.
Loose labels on cassette tapes can become
lodged in the mechanism. Remove any loose
label material before inserting a cassette.
Do not leave a tape in the cassette tape
player when not in use. High heat in the
vehicle can cause the cassette to warp.
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