This is just the latest in a long line of calls to my landline originating from an 01382 code (Dundee), although I've also had a couple from Glasgow. Whenever I dial the numbers from my mobile they always come back as invalid. As fast as I block them they keep coming back from the same area. I never say anything when I pick the phone up, always waiting for somebody at the other end to speak first. They (or it) always hang up, indicating that it is coming from a voice-activated, automatic spamming or scamming system.