Volvo: Volvo S60 air conditioning, climate control system, volvo service

Question
I have the climate control system in my car. I have been setting the temperature at 68 F. When I start out it seems to be working fine. However, after about 10 minutes of driving the air flow is from the vents is drammatically reduced. I can manually turn up the fan speed and the airflow increases but it is not close to what it should be although the fan seems to be working OK. The more I drive the worse it gets. If I stop and leave the car sit for a while then it will be working fine when I start out again. The air that comes out is extremely cold. When the air flow is cut off you can feel the cold air come out of the vents and fall straight down the console. A couple of times there was a little bit of fog coming out of the vents. I have the car at the Volvo dealer and they keep telling me that they can't find anything wrong. What do you think is causing this?
Thanks!

Answer
Mike,
It sounds like the air mixture motors are in need of calibration. Possibly the blower motor is at fault and begining to fail. If this occures each time you drive the car have the dealer send the tech out for a ride with you so you can show him the problem. If all that fails ask to have an appointment with the Volvo service rep from the manufacturer and take him on the ride.