iTunes keeps asking to verify payment information

I am using 9.2.1 (although this problem started with iTunes 9.2 sometime) and iTunes keeps asking me to verify my payment information whether I am using my iPhone, iPad or my iMac. I verify and the transaction goes ahead. It does not matter whether it is a free update for an App on my iPad or iPhone or purchasing music or a TV Show on my iMac. The error message is that a transaction has taken place on a new device or computer and that it needs to verify my payment information.

The verification lists my card data and address etc. correctly but I need to keep entering the card security number.

Support keep telling me to delete and re-enter my car info which does not help. Anyone else seen this issue?

Seems to be something to do with a new security check they have put in the system that does not work correctly and support is totally incapable of helping me out.