4th Gen 2020 M1 Mac mini bluetooth issues with Magic Mouse2

Personally, I'm thinking that the fact that some techniques minimize the problem but don't work for others indicates that there may indeed be an "electronic environment" issue.

In my case, I have one home automation item that uses 2.4ghz only (and it's not that old) so it is not realistic to turn off the 2.4 Ghz item (though I did try that as an experiment, and even with the 2.4ghz band on the wireless router turned off, I still had the drop offs).

I'm happy for anyone who can get things to work for them. Again, I will say that my work around has been not to use a mouse - the trackpad issues for some reason are less (not nonexistent, but less), so that at least I can use the computer. However, the frequent drop outs with the mouse did make the computer unusable, so I do understand the users that haven't had a fix are very frustrated - no one wants to pay good money for a computer they can't use (or have to buy a bunch of extra peripherals that also don't work).

If the electronics environment is the issue, I'm not sure I understand how software can fix that. Maybe better communication protocols? Is there a way to filter the noise out of the signal with software, or strengthen the connection? Debouncing? Checksums? (I know, my ignorance is showing).

This is pretty much the behavior we are all experiencing.

There are two types of issues:

1. Mouse disconnections, which happens almost randomly every few hours and lasts about 10-20 seconds until it is finally useable again. This happens with "mouse disconnected" messages being displayed.
2. Mouse lag/stutter where you either hover over certain elements (the sound menu being a known one) or having your iPhone wake up from sleep (most commonly because of a notification). In this instance you don't see any messages, but the mouse is indeed lagging for at least 10 seconds.

I have the same issues with my Magic Mouse. On other Apple MacBooks I have no issues with the mouse.

Another thing I encountered twice in the past three weeks. When you wake up the Mac Mini and you try to enter your password, each keystroke is entered 4 or 5 times. Hard reboot is the only fix for this (as you cannot shut down your mini from the login screen (why?!)).

Following up on my previous comment, hoping that I may have found a solution, unfortunately it hasn't worked and the Bluetooth connections are dropping again.

Apple really need to make an announcement about this urgently or they are going to have a mass return on their hands. Unless you use a wired solution or a Bluetooth dongle, then the Mac mini is virtually unusable.

This is really not good enough from Apple and not up to their usually excellent levels of customer service and, frankly, their online support has been absolutely useless. This needs to be sorted out quickly.

Absolutely the same issue.

Apple! DO SOMETHING WITH THIS.

Btw here is the log from Bluetooth Explorer (without personal data).

As your can see the total time of connection drop is around 8 sec.

Number of Host Controller Disconnects 0

Magic Mouse - 00-00-00-00-00-00

Number of HID Disconnects 6

Connect Tuesday, 01-19-2021 04:00:50:929 PM

Disconnect Tuesday, 01-19-2021 04:00:49:615 PM

Disconnect Tuesday, 01-19-2021 04:00:49:615 PM

Disconnect Tuesday, 01-19-2021 04:00:49:615 PM

Connect Tuesday, 01-19-2021 04:00:44:315 PM

Disconnect Tuesday, 01-19-2021 04:00:43:352 PM

Disconnect Tuesday, 01-19-2021 04:00:43:352 PM

Disconnect Tuesday, 01-19-2021 04:00:43:352 PM

First Seen Tuesday, 01-19-2021 10:29:42:271 AM

Number of Host Controller Disconnects 0

Just an update: Since encountering the Bluetooth drop outs between my M1 Mac Mini and Magic Mouse 2 and Magic Keyboard 2 maybe two weeks ago, and shutting my Mac down overnight, I have not encountered any further drop outs. I also did update my Mac to Big Sur 11.2 beta 2, as well as iOS 14.4 beta 2 when they were released. No further drop outs. So this leaves me still wondering what are the triggers to the BT drop outs, and what, if anything, did I do to stop the drop outs. I just hope the drop outs don't return as they did for others in the Apple Community.

Yeah, something weird is going on. I had to switch to my PC today while working from home, as the keyboard was inputing extra characters on its own - couldn't answer any emails. I've done all the same things as you - shutdown over night, I have gone through all versions of Big Sur including 14.2 beta 2, and obviously, hasn't helped.

What I find interesting is that folks are having success with the Asus Bluetooth dongle. If it is the electrical environment, why does that dongle work and the internal bluetooth not work? Also, it seems that older Mac Mini's also have bluetooth issues, and at least the last Mac Mini uses the same Broadcom chip and there are also reported bluetooth issues with that system as well (but I haven't looked to see how widespread those issues are). So is it the broadcom bluetooth chip? The antennae for the bluetooth module? Does the metal case block too much of the signal, and the external dongle works better than an internal chip/antenna? Looking to you engineers to shed some light on it. If it is the bluetooth/hardware issue, I'm not sure that an update to the OS will ever be able to solve anything (unless they have a way to boost the signal)?

I was one of the original posters on this massive thread. My problem basically disappeared for a while -- only occurred with Magic Mouse 2 (I also have Magic Keyboard and Trackpad) once every 3-5 days.

It has now come back, still not severe (once or twice a day). I've tried a few of the fixes here (turning off Handoff, turning off WiFi since I'm connected by Ethernet), and nothing worked.

I now notice a reliable pattern. The problem occurs in pairs: disconnect/reconnect, pause, disconnect/reconnect. Then it is fine (for quite a while in my case). Has anyone else noticed this pattern of pairs?

I posted a comment earlier in this thread, that for me the lag stopped with Logitech mice when I connected them by their own Unifying receiver via USB 3.0 hub. I got terrible lag with the receiver connected via USB 3.1 hub earlier.

So I'd also think that this is somehow connected to USB data rates etc, but it's beyond my expertise to investigate and comment reliably on.

Interesting. Testing without the ASUS BT400 (using onboard bluetooth) and an older Magic Mouse (battery powered) and it is working so far. Even the unlock mac is working.

Starting to wonder if Magic Mouse 2 is part of the problem as I tried two different ones on my mac mini and same issues with both? We'll see if my keyboard starts stuttering again or if the mouse disconnects. Just hooked it up a couple minutes ago.

I'll update if I have problems.

P.S. I also checked the bluetooth with both istumbler and Bluetooth Explorer and didn't see any big differences between the two bluetooth modules.

That's what concerns me; it seems that this problem has been around a while, and in my mind, it points to a hardware issue, not a software issue (you would hope that they would have fixed it by now if was software, right?).

I don't know what bluetooth chip is in your 2008 (you can check from Apple->System Information-> System Report, but you probably already know that ;), but the previous iteration of the Mac Mini uses the same Broadcom chip, and reportedly has the same issues (to what extent I'm not certain).

In my mind, it is pointing to a hardware issue and not software, but I'm not engineer.

I've been with Apple from almost the very beginning (an Apple II with 16K RAM, those were the days!), and I also feel a bit let down in recent years, as well.

That's a different Broadcom chipset, I believe.

So, if your 2008 has the same issues, makes you wonder if it is the case or the antennae, huh?

OWC has a product that shields the bluetooth antenna on a 2012 Mac Mini (to protect it from USB interference), you may want to send them a note to see if that will also work on the 2008. I think it was about $12, so doesn't cost much. I was going to contact them and see if that could work on an M1, as that has also been an issue for some people.

I'm kind of getting upset that this issue seems to be present in a lot of generations of the Mac Mini; if it is the "electronic environment", then how come Asus's USB BT 400 external works so much better? Wouldn't the "electronic environment" be about the same for the bluetooth dongle as it is for the Apple bluetooth module? Is it the fact that it is external what helps? Can the Bluetooth/Wifi antennae be externalized on the M1? Something isn't adding up here....;

I think one of the best ways to directly make Apple engineers aware of your issues is to participate in Apple's Public Beta or Developer Beta testing. As a beta tester, you have a "Feedback Assistant" app from where to enter your bug issues in detail, along with automatically generated system logs. As a developer beta tester, I have submitted many bug issues and have received responses directly from Apple engineers when there was a bug that was not previously reported or has been relatively puzzling to solve. Be assured that your bug reporting through the Feedback Assistant will be considered in Apple's data gathering, and possibly acknowledged directly from an Apple engineer.

I don't remember seeing this here but I just downloaded the Bluetooth Explorer and I am seeing multiple errors of the same type:

Apple80211Get(APPLE80211_IOC_BTCOEX_MODE) returned error -3903

updateChainPower error: -3903

From a general search, I see this error has been reported multiple times in the last year in connection with Bluetooth disconnects. Does anybody know if this could be a clue to the issue here? I didn't notice any issues with my BT devices while this error was reported but I have had a very few Trackpad disconnect in the last couple of days.

Here is my response to Apple engineering, via Feedback Assistant app (Apple Developer/Public Beta Tester program):

As of January 10 2021, the date when I submitted the Bluetooth bug issues with my M1 Mac Mini, I have not experienced any further disconnections after shutting down my Mac Mini overnight and restarting the next day (Jan 11, 2021). I did download 11.2 RC 1 and continued not having any BT issues whatsoever. And after downloading 11.2 RC 2, I also continue not having any BT issues. There are many Apple M1 owners complaining about the M1 BT issue on the Apple Community Forum. People there are very frustrated as they believe Apple is not taking this bug seriously. I hope some Apple representatives will review the office Apple Community Forums and ultimately make a clear and concise public statement that addresses the BT issues directly. The latest RCs did not conclusively state that the BT issues have been fixed.

Hope this gives community members a little peace of mind.