Can't make calls after FROYO update??

Happened to me as well. Verizon tech had me change a number in some hidden system menu. Loon and the short of it, the update screwed up my location and the phone thought it was in another part of the country. After I switched the number my calls have gone through just fine.

What was that secret number?
 
This happens to me after using the media player for an extended period of time. It happened again today and I just happened to be near a Verizon store so I took it in. After two reboots, the first reboot stuck on the moto logo, it was working again. Tech couldn't duplicate the issue but did note my account. Then she suggested and downloaded the froyo task killer onto my X. I took back the phone and uninstalled it right in front of her telling her that a task killer will likely make matters worse.