go in and out
1. To move quickly between places or things. Kids, quit going in and out of the house—you're letting the bugs in! That fool is going to get into a car accident with the way he's going in and out of traffic.
2. To function properly or ideally only intermittently. Often used to describe electronics. I'm sorry, honey, I can't hear you—the sound on my phone is going in and out. Move the antenna, the picture is still going in and out.
go in and out (of something)
to pass in and out of something or some place. The nervous little mouse kept going in and out of its hole. The cat kept going in and out of the back door.