Since updating to version 1.4.8 repeatedly a weak signal occurred on short distances. I've never had this problem before. Even not in areas where you may expect interferences. What's going on? Do I need to go back to 1.4.4?

Countdown to the gratuitous:  "Sorry for the inconvenience. Please make sure you have most current firmware installed for said drone and said controller".

Several users have reported issues with DJI Fly App V1.4.8.  I had issues and uninstalled V1.4.8 and reinstalled V1.4.4 and signal issues went away.  

You can find all previous versions of the DJI Fly App here.

DJI Fly App

MBSL500 Posted at 8-2 12:55
Countdown to the gratuitous:  "Sorry for the inconvenience. Please make sure you have most current firmware installed for said drone and said controller".

Very sad the information from OPS here.
No real comunication with DJI... Only like bots.
When solve this people the problems with 1.4.8?
When be avalible 1.5 ?  

Abel nt Posted at 8-3 09:10
Very sad the information from OPS here.
No real comunication with DJI... Only like bots.
When solve this people the problems with 1.4.8?

When the Mini 3 is released  

Abel nt Posted at 8-3 09:10
Very sad the information from OPS here.
No real comunication with DJI... Only like bots.
When solve this people the problems with 1.4.8?

And this will continue as long as forum members continue to "thank" DJI when they post canned responses rather than call them out for it.

I think signal issues are related to latest Mini 2 firmware and not the app itself.

To be honest I'm not really sure if the signal problem is just firmware related. The signal is displayed on the app, so the signal is somehow interpreted by the app using the DJI SDK.
Before there were two types of signals displayed on the APP: that of the RC and that of the Ocusync video, called HD.
Now the signal is unique.
If for any reason the App fails to decode the video signal, what the smartphone does and not the remote control (frame corruption, processor slowness) what error does it return? Does it ask for a frame repeat? The drone can interpret this as a lack of signal.

I should do some comparative measurement between the DJI Fly app 1.4.8 and maybe, dronelink or litchi or maven. Both use the DJI SDK but the app's processor usage is different.

Raf_IZ0QWM Posted at 9-20 11:24
To be honest I'm not really sure if the signal problem is just firmware related. The signal is displayed on the app, so the signal is somehow interpreted by the app using the DJI SDK.
Before there were two types of signals displayed on the APP: that of the RC and that of the Ocusync video, called HD.
Now the signal is unique.

Since I've updated the app 1.4.8 into 1185 (instead of 1120) not any weak signals anylonger. I really suspect the app.

Robert20 Posted at 9-20 11:46
Since I've updated the app 1.4.8 into 1185 (instead of 1120) not any weak signals anylonger. I really suspect the app.

Yes I'm pretty sure about it.  
I replicated some of DJI's FCC tests in my office's EMI room and found no differences in radio emissions. So there is no change in TX power.