Since I've I've had my 3rd Spark (1st 2 flew away) it has only used the 5.8 GHz channels in auto channel select mode. I was losing connection at ~300-500 feet. I flew my previous Spark over a mile with no loss of connection. I sent it back to dji where they replaced the main board under warranty. However it is still selecting a 5.8 GHz channel, though I haven't yet flown more than ~100 feet. I understood someone in tech support say that it didn't switch to 2.4 GHz until it was far away. I'm not sure if I understood correctly as there's a bit of a language barrier.