How 2 Get Gps To Lock In. 3 Phones Won't Lock. Gps Test App Says Low Signal

We have 3 Samsung Admires that won't lock in on GPS.  It's either a phone issue or a software issue....  It seems when I use GPS Test app only 2 to 4 sats are being viewed but not with a strong enough sig to use them.   I've been many places in Hagerstown and in DC this pas week and only had it lock like twice ever and I've tried a lot.  Tried enabling and disabling many settings including Using Networks and using Home Only etc.  I also did a factory reset on one of them.  Nothing has helped.