Thx t65d
I've tried an Android phone and another tablet. Both tell me "signal lost" as soon as there is a connection to Litchi. Set the connection type to RNDIS (USB Ethernet), as I always have and that is having no imact on sucess at all.
On the tablet I use with Litchi, a Samsung Tab S2 (model SM-T713), is "Disconnected" as soon as it opens up. I then (as have had to so many times), go back into Dev Options/Select USB config and set RNDIS as it always slips out of that setting from the first setup time. Reset it and go back to Litchi normally secures a connection but not any more.
