iPhone 15 Crackling Due to Speaker Hardware Limitations

Confirm this cause by testing the device's audio output with high-fidelity reference audio at volumes exceeding 80%. If the crackling is consistent across various apps and persists after removing all cases, screen protectors, or physical obstructions, the issue is likely rooted in the physical threshold of the speaker hardware. Verify if the distortion is present during system sounds at these high levels, confirming that the speaker diaphragm is reaching its mechanical limit in handling specific frequency ranges.

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