salmirsd,
This is a bad time of year for Political Survey calls and people calling for $ contributions from charity organizations. These calls are auto-dialed via Call Center Technology which means that quite often the human caller on the Call Center side of things hasn't readily heard the tone in their headset indicating that you (the recipient of the call) answered the phone. They typically won't connect unless there is an answer on your end. Quite often they are goofing off, sipping/swallowing a drink, or talking to their fellow employee, etc., and don't connect right away because they failed to hear the tone in their ear indicating you have. If you want to try something sometime, and you know it's one of those "UNAVAILABLE" caller-id calls, pick up the phone, stay silent for awhile, and then snap your fingers into the mouthpiece of the receiver. Then they will answer and you can hang up on them.
That might be what you are experiencing. Nuisance callers rarely will show you their callback number ... that way you have difficulty blocking them. Just a thought for you to consider as to why this may be happening.
Hope this helps.
