For a long time I stopped answering my telephone (landline) because the overwhelming percentage of calls were marketing. I've started answering some calls lately, and I don't understand what's happening. I answer a call, and all I hear is several seconds of dead microphone, then a click and the connection is broken. They aren't the typical robo calls, because there's no canned announcement that starts playing as soon as I pick up. These are strictly just dead air, then disconnect.
Has anyone else experienced this? Do you have any idea what it's about?