I'm echoing the OP on this, I received my H4 a few weeks ago (early Sept) and have nothing but problems with GPS lock. It worked perfectly the first time but hasn't worked since. It's interesting that the OP says his worked up to July of this year, and mine is having problems from the get-go; similar timeframes suggest a problem with their firmware's GPS lock (I updated immediately to 3.0.44 upon receipt). I've searched their support site for answers and have done the 1 fix they give (linked by tony above) multiple times with no success. I'll be sending a detailed email to support & will report back here with their response (hopefully).
