Strange noise in cabin

UltraIron1

Hey all;
I have an '09 Nismo 370Z with @ 8,000 mi. on it that I've had since May of this year. For the first four months that I had the car this issue never occurred. Beginning in Sep't., when the car is parked overnight or all day without being used, at start up when you begin to drive away there is a "clicking" sound coming from under the dash on the drivers side. The clicking follows the RPM's of the engine and only lasts for about a minute. Also, it seems that with the cooler weather the sound has become a bit louder when it happens. I'm very interested to know if anyone else has experienced this noise since I had a technician ride with me and his reaction was "never heard anything like that before" but the shop foreman is trying to tell me that "it is normal" for the 370Z!!
Thanks for any info.