It's clearly an automated call. As soon as you answer, they just cut the line.

While on holiday overseas, I received a staggering 14 missed calls from this number in just two days. Assuming it was something important, I eventually decided to answer. Turns out, it was just Car Phone Warehouse trying to get in touch!

I received a call from an unknown number based in Esher at 5:34 this evening. Honestly, I don't have a clue who it was, and I can't say I'm expecting anything positive from it.