logitech k400 not working with nvidia shield

[Android Central Question]

I bought the logitech K400 several months ago to use with my Nvidia Shield, and it worked beautifully...until now. After this latest update the keyboard no longer works. I've tried everything short of a factory reset, which I really don't want to do. I've replaced batteries, made sure USB debugging is off, and verified that the keyboard works just fine on other devices (such as my Asus laptop).

Is this a known issue?

 

[Rukbat]

At very least, you'd have to plug the receiver into the phone (through an OTG adapter or cable). Logitech unified protocol isn't something that Android normally picks up. (Why it worked before is a mystery.)