2 faulty 1708 boards,,,, which is easiest to fix using the other maybe ;-)

[theADDict]

ok, two dodgy 1708.

thanks for pointing a newb to what could be the issue RDC

main pcb one.....wont connect via bluetooth to console.
maybe will for one second, then loses instantly
Swaped with another power board, same result.

pcb two....connect to testing app, usually shows nothing until you press a few buttons then whammo....both sticks go to bottom right  and wont move.
all other buttons and stick centres then respond....except stick movemenat and triggers !!!!
connects to console via sync fine.

whichever you think easier to diagnose, will use other for donor parts.
but have other donors too.

[RDC]

Any wireless issues will be on the SoC board of the bottom board or a shorted/broken antenna cable/connector. Lots of tiny parts on that board that make up the filter networks for the antenna circuits. If it all looks good on there and compares the same to a know working board, then about all that's left is the MCU causing the issue.

Sticks and Triggers get their power from different places, so for the Digital (buttons) to work and the Analog (Sticks/Triggers) that seems like an MCU issue of some sort.

I'd try a firmware update on those things first since the issues are on the bottom boards.