• During receiving and outgoing calls, the speaker button may also be greyed out. Other symptoms include no audio when voice memos or movies created by the affected iPhones are played back.
• Disconnecting any Bluetooth or other audio accessories, as well as performing audio diagnostics, are all ways to troubleshoot the problem.
• According to the text, if the equipment is out of warranty, an exception may be available, albeit this will depend on the circumstances. It's unclear whether this indicates a complete unit replacement or a repair to fix the problem.

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