GeoChron Blue - Intermittent Initialization

My GeoChron Blue sometimes “hangs” on the Green LED during the startup initialization (Red=OK, Green stuck on, No Blue). I know the User Guide says this indicates a problem with the EM408 GPS Module. The thing is, the Red, Green, Blue LED startup sequence works most of the time.

Does the EM408 need to have a good signal from the antenna during the brief startup initialization (I would guess this is unlikely, since a good initialization only takes a few seconds) , or is the EM408 portion of the initialization (Green LED) just checking the data link between the EM408 and the GeoChron Blue microcontroller ?

Any help will be appreciated. :?