Dotted red lights mean that night vision mode is active - i.e. the Hello doorbell has determined that it is past dusk, and so it has enabled night vision so that it can still record visitors in the low (or no) light conditions. If night vision isn't enabled (either it's disable in the app, or it's not yet dark enough) then there's two other possible causes: 1) A software or hardware bug has meant that these lights have turned up by mistake. 2) It's cold outside! Some internet rumors have speculated that the (warm) infrared based lights might be turned on to keep some of the internal sufficiently warm when it's colder than usual. This hasn't been officially confirmed, however.