Hi guys,
first to answer the question regarding 2,4ghz.... you can switch it inside the application by clicking on 2,4 and choosing the channel to use with 2,4 ghz.... its normal that after choosing 2,4 ghz the drone and app is restarting by itself and in that few seconds the app becomes colorless in black and white mode...
Also check the app version you have, because I have .14 version...
I am using for the last three months these firmware:
RC .400
Drone .300
application .14
I found that the 0.300 drone firmware is the most stable of them all , everything works without any problems... all these new firmwares DJI is giving BS that its improving bla bla, while the reality is each new frmwr is declining what you can actualy do with your drone... limiting use of OTG, introducing NFZ and all other crap... I will never update to any other crap from DJI , will just stay on 0.300
and as for me this is the last DJI drone I bought, its just ridiculous to pay that much money for DJI products and then they limit you heavily in which way you will fly or use your drone... fckng criminals