Leaving the call hanging can lead to billing issues because the application is unable to process incoming call hang-ups when it is stuck waiting for a response message.

保持调用挂起可能会导致收费问题，因为当应用程序受阻塞、等待响应消息时，不能处理入站调用挂起。

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When an incoming call or message arrives, it can be received via voice command without even touching the phone.

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Effectively, the machine is checking for news of an incoming call or message briefly once every 15 milliseconds before powering back down, rather than keeping connections to the user's peers constantly open.

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