Intermittent severe Magic Keyboard lag

I have gone through my peripherals, an it seems the culprit might be my Logitech Master MX 2 mouse, wireless via a small USB dongle. When I use an old cable mouse instead, I don't experience any lag at all.

I have used the Logitch mouse via a USB-C-to-"old USB" adapter. Hard to say whether the adapter, the mouse itself or the dongle is to blame. Regardless, things work fine after "de-Logitechisation".

Has anyone else experienced anything similar?

Note: still only, or at least mostly, in Apple's native apps like Mail, Notes and similar. Veeeery strange.

And never mind what I just wrote about the keyboard being faulty. I just had the problem with my old keyboard too.

I think I have noticed that, for some reason, the "accent popup menu" appears just before the problem starts. The menu is supposed to appear after a prolonged depression of a key, but for me the menu appears – now and then – at quick strokes.

Not knowing whether the menu is an effect of the problem or if it is actually causing the problem, I have now disabled the menu since I never use it. It is possible by writing "defaults write NSGlobalDomain ApplePressAndHoldEnabled -bool false" in the Terminal and then restarting (or maybe logging out is sufficient).

I will try this and see if it helps.

mestor wrote:

1- Factory Rest all apple devices

2- Reset the Bluetooth module

3- Remove all devices.

4- Reconnect all devices.

Did this a week ago and everything's been fine since. Many thanks, mestor!

Never mind what I wrote about the mouse. The problem appears even with my 15-year-old cable mouse.

I have now concluded that the keyboard itself (Apple Magic Keyboard 2 with numerical keypad) is the reason for this strange behaviour. When I use my old keyboard (an older Magic keyboard without the numerical keypad) there is no lag. I will return the new keyboard as faulty.

Barry, have you tried disabling the accent menu with the Terminal command above? Took care of the whole issue for me. Therefore, I marked that as the soultion to my problem (privilege of the TS). If it doesn't do the trick for you, there are obviously multiple reasons for this obstructive behaviour.

Note that disabling a function cannot really be regarded as a solution, but for me, never using accents (almost absent in Swedish), living without the function is not a limitation. Apple, if you're monitoring this, please check the behaviour of the "ApplePressAndHold" function.

I have also reverted to a wired setup: I have connected my Magic Keyboard with the charge cable and disabled the Bluetooth connection. Haven't seen the issue since. So, there's something fishy with the wireless connection.

It's interesting to see that you're getting the same lag with a Logitech dongle. That suggests that the problem is "above" Apple's own Bluetooth connection, if I'm not totally wrong.

I can confirm now that I have absolutely no lag issues at all when I connect the keyboard with its charging wire. So it is my BT connection that is shaky. Will talk to support (the computer is only a few weeks old).

I am happy to have identified the problem, but I am growing totally mad over the fact that the keyboard auto-connects (BT) every time I wake the computer from sleep. Haven't found any way at all to tell the computer to ignore the connection attempts.