Just a few ideas. First, the time it takes to pick up satellites will vary tremendously. This is a factor of the GPS system itself, primarily. In theory, if you have moved a long way, or have not been flying for a while, it could take up to twelve minutes as the system loads it ephemeris data. A red light or two is not a problem after you have locked on, the number of satellites the phantom can see is dependent largely on the constellation geometry and there will be times when 6 plus are not visible, or when the receiver is changing the satellites it uses in its nav solution. When you change battery after flying once, the nav solution should be achieved very quickly as the receiver "knows" what satellites to look for, and already has timing corrections and emphemerides data. My advice, when flying somewhere new, is to allow plenty of time for the first "lock on" and to use some sort of GPS prediction app(there are several free ones available) to ensure that the constellation is configured so you have the right number of sats available. If local takes a long time, disconnect and reconnect the battery which will restart the acquisition process and should give it a kick. Most of all, the phantom can only see sats that are.... a. There and.... b.within line of sight so check the planning data and make sure you have an unobstructed view of the sky.