Could someone please help me with this issue

I just bought my Treo 650 from Cingular 2 days ago. Now, when I switch between 2 Apps - like Calendar to Phone, etc., there is a long 30 second delay when the screen is just blank, but lit up until the next app shows up. Is this a ROM issue? If so, how can I speed things up. It just started happening.
I have 16 megs free, and the phone info is:
Treo 650 1.04-CNG, Firmware 01.05
Thanks for helping the ignorant.
JT