Hullo, Hullo, is there anybody there. Huloo!

Twice this week, I have answered the phone, and said hullo twice, to dead silence, then the caller hung up. No sound, no heavy breathing. Nothing. I am a bit concerned about it, as it could be someone 'casing the joint', or, it could just be some rude punk who has not got the good manners or sense, to say, 'sorry, wrong number' It might also be one of those niucisance calls from the sub continent, wanting me to change my phone company.They drop out sometimes. It could also be kids, playing silly buggers.How-some-ever, no point in worrying about it.I will worry about it when it happens every day, which I don't think will happen.