I've had my Mavic for about a week and have flown 3 batteries almost every day.

On Friday night I updated the firmware to the latest version and went flying again on Saturday afternoon.

Shortly after takeoff the info bar at the top of the DJI Go4 app said "Aircraft Disconnected', but everything was still working prefectly. I kept it very close to me in case something happend and landed it before the battery got close to 30%.

I then changed the battery and flew again up to 700 metres away without the error message.

But the same thing happened again yesterday. This time I just flew it normally up to about 500 metres away without incident.

Does anyone have any idea what might be going on? I was just starting to develop some confidence in the system.

I also have a couple of other problems that may or may not be related. Firstly, for the first few days I was really impressed about how reliable the video link was. Almost no lag, but for the last few days the lag has been quite bad, sometimes several seconds. This doesn't The record button is very slow to respond when this happens too. The remote control is still perfectly responsive at these times. This has happened at several locations, all of which I'm pretty confident don't have any strong radio sources. These places had no problems in the earlier flights, but the lag is there on every flight now to a greter or lesser extent.

My phone is a Samsung Gallaxy S4 and if this had happened from the beginning I would have assumed my phone was just underpowered for the Go4 app.

The other thing I've seen happen twice now if the gimbal has suddenly reset and made some odd movements, almost as if it's decided to do a calibration, although this only lasted a few seconds.

Both of these other things have happend both before and after the firmware update.

do you have upgrade all of your batteries?

I don't know how to tell for sure. When I performed the upgrade I powered down everything, changed the battery and started everything up again. For the second battery Go4 told me there was inconsistent firmware and updated, but for the third battery there was no message about firmware. And each time since there have been no firmware related messages.

What is the APP version? Have you tried to reinstall the APP, then run it when your phone is in the airplane mode?

I updated at the same time as the firmware update. 4.1.9

I updated to the Go4 app to 4.1.10 and flew it again today. Only one battery.

No message about the aircraft being disconnected, but all the telemetry data was delayed by about 20 to 30 seconds. The video link and controller were responsive.