Hi,
I have a master remore control (Apple - mini 4) and a slave (crystalsky).
I updated the  firmware of the aircraft with only the master connected and now I can  not update the slave ... On the screen of the slave I see the message  "update required" but when I click on this option the screen of the  slave becomes dark. The light on the aircraft flashes yellow when I have the "master" and the "slave" connected to the aircraft.
How can I update the slave firmware?
Thanks.

you need to turn off the remotes when you update the inspire. then turn off the inspire and update each single remote with the other one being off

Walter, besides TruGreen's suggestion, please connect to iPad Mini 4 to see if it works.