Before the quarantine started, I decided I needed a proper work space at home for my new 16" MBP. A monitor, desk, keyboard, etc. Working from the couch on my laptop just didn't cut it in terms of screen space and ergonomics. So I went out and bought everything including a new Apple Magic Keyboard and Magic Trackpad 2. Than

Unfortunately, I found the keyboard to be somewhat laggy. It was only a minor annoyance when working, but frequently having keypresses queue up and take a few hundred extra miliseconds to appear is annoying... and makes gaming impossible. So I ended up hardwiring the keyboard and found the mouse to be okay. But at the same time, that's kind of BS. I bought the 16" MBP and a USB-C monitor because I wanted exactly 2 cords on my desk: Power to the monitor. And the monitor USB-C to the laptop to provide video and power. After spending several grand on this setup, it just didn't seem right to need a cord to keep my keyboard plugged in.

So how did I fix the lag?

Eventually I contacted Apple. They suggested the usual stuff. Turn the bluetooth devices and radio off and on again. Restart the computer. Make sure the devices are well or fully charged. Forget and pair the devices again. When that didn't work, they suggested I reset the SMC. Twice. I offered to try resetting NVRAM, because why not? Those may solve most issues, but they didn't help me.

Here's what did help fix my bluetooth lag:

  1. Hold shift and option on your keyboard, then click on the bluetooth system menu.
  2. The debug menu should appear (which you wouldn't see without holding shift and option).
  3. Reset the Bluetooth module
  4. Repeat steps 1 and 2 and then factory reset all connected apple devices.
  5. Connect/pair the keyboard and mouse again.
Hold shift and option when clicking the bluetooth system menu icon to access hidden debug options and info.
Hold shift and option when clicking the bluetooth system menu icon to access hidden debug options and info.

The result

With that done, suddenly both the mouse and keyboard work flawlessly with no lag.