Mouse suggestions welcome too, if the keyboard doesn't have a trackpad - the Logitech G602 "Lag-Free" (ha!) Wireless Gaming Mouse, with it's dongle literally 1' away ALSO lost friggin signal constantly and skipped across the screen all laggy.
To rule out my computer hardware as being the issue I've tried all of the below on a Lenova Yoga Win 10 laptop, my brand new HP work laptop, my mini-ITX GroovyMAME computer I built with ASRock H270M-ITX/ac motherboard (w/ BT v4.0) --this will be the main computer to use this on now, and 3x different Macs (Macbook Air, Mac Mini, Mac Pro from 2009 to 2016 models). ALL had issues with connecting, staying connected, and dropping button presses left and right (pun intended lol

FAILURES:







(and numerous other even smaller ones I use on my Raspberry Pi setups).
The 3' line of sight setup was in my server rack in my game room - if 2.4g I had the USB 2.4g dongle on a USB extender right on the front of the server rack 3' away from my desk I was typing on. If using bluetooth the actual computer was on top of the 7' tall rack, and it was 6' line of sight. With the laptops we're literally talking like 10-18" away... sometimes actually touching. All the retro consoles in the server rack are so old none have BT to interfere (and modern wireless controllers are all turned off).
The second common setup, and what I plan to use this new keyboard on now, is my living room. I'm 10' away from the computers sitting on my entertainment center while I'm on the couch. The only things turned on is the TV, Denon A/V receiver (which has BT capability but not using it), Mac Mini (media computer), and some lamps are turned on. I ALWAYS have my Mac "Magic" keyboard and touchpad on (these are the only ones that actually work fyi) but that's it. No tablets turned on, everything else in the entire house turned off, nothing else in use but my cell phone.
I do have WiFi in my house, it's on a stock Verizon router in the garage, ~25' away. My cell phone and Nest thermostat are connected via WiFi and that's it. Everything else in the entire house is hard wired ethernet (16-port ethernet switch in living room, 6-port in gameroom, 2-port 'ethernet over power line' in the upstairs bedroom, currently unused (oh, there's an ancient flatscreen upstairs with a Fire Stick using WiFi - I think it might be turned off when the TV is turned off as it usually is though).
Sorry for all the stupid detail, but I'm mentioning this kind of info to help troubleshoot and hopefully show that there shouldn't be enough interference in multiple areas of my home to make not a SINGLE wireless keyboard work (except the single Mac Magic keyboard). Like this is friggin crazy... THIRTEEN OF THEM, and NONE work!!! In two separate areas of the house. It's been a bane of my existence for 10+ years now (and WIRED, across a living room isn't going to work). Looking to finally start using my GroovyMAME computer (and it's crazy deluxe HyperSpin on its other partition my buddy built for me), but can't do this without a keyboard. I've been watching my brothers kid too much to have keyboard/mouse wires laying around the house for him to trip on, so again wired isn't an option.