LPT: When answering a suspected spam robocall, pick up and remain silent for two seconds before saying hello.

Most automated robocallers have a built in program to help distinguish the phone numbers of real people vs the phone numbers of other automated phone systems.

There's no sense in robocall spamming a number where no human is listening.

If the robocaller doesn't receive an immediate response when the connection is made, it flags your number as not a real person, it doesn't play the automated robocall message it normally would, and auto hangs up after about six seconds.

This effect also helps cut down the frequency of robocalls in general.

If the call is from a real human being, they will wait through the two second pause.