MacBook Pro M1 WiFi issue

This may be a little long but hopefully worth it for those of you using USB C hubs.

I had the same issue with my new 2021 MacBook Pro M1 Pro (and posted about it previously). It was intermittent, though. Ethernet still worked like a charm. They were very nice at Apple support, but they could not figure out the source after a bunch of calls. Because it was within my 90-day return period at Costco, I returned it and bought another one, figuring it was a bad wifi antenna. Now, the same thing is happening with the new one, but mainly right after it comes out of sleep (which is different behavior). I "usually" can resolve it by toggling my wifi on/off or restarting the machine. (So, I'm feeling a little guilty right now, which you'll know why after reading below because I otherwise loved that machine ... and I have been a Windows guy for the longest while.)

This morning after waking my machine from sleep, the same thing happened. Coincidentally, I was shopping yesterday on Amazon for a USB C hub for my daughter's MacBook Air and read one review that complained about the hub interfering with wifi connectivity. On a hunch just now, I unplugged my own USB C hub, and voila, my Speedtest.net download speeds returned to normal (e.g., 350/380 Mbps). I plugged it back in, and everything gradually slows down (eventually dropping to 1 Mbps to 25 Mbps). I repeated this process multiple times just now with the same consistent response.

My current setup is a USB C hub plugged into the USB C port on the right side of my machine. Connected to that hub is a powered USB-A hub. (I tried just now stretching the cords to their full lengths to create some separation, with no change.) Between the two hubs, I have connected the following devices: HDMI monitor, wired Logitech keyboard, wired Logitech mouse, Logitech HD 1080p webcam, Envato Wave 3 microphone (which is very new), and a Wacom tablet (just connected the other day for first time). I am using the HDMI port on the right side of the machine (so I can have dual monitors). On the left side, I have an SSD connected via USB C (also recently connected), and the audio jack connected to external speakers.

Things are sorta better now on their own, which typically happens, but not great. On a side note, once the problem occurs, Safari has a much harder time bouncing back than Chrome does, at least this morning it does. However, I just tried unchecking "Limit IP Address Tracking" as suggested above, and Safari is doing better than it was - now 185 Mbps on average versus Chrome's average of 220 Mbps. Neither of these speeds is as good as my top speeds without the hub plugged in.

On another note, I have no bluetooth devices connected to my machine (or hub). I disabled bluetooth anyway, but it doesn't seem to improve things back to the 350/380 Mbps range.

I will continue to diagnose and see if I can pinpoint the actual device causing the problem (which is probably the USB C hub). I may order a bunch of different hubs, but if you want one with a lot of ports, they're all third-party. I shelled out $69 yesterday to buy Apple's own USB-C Digital AV Multiport Adapter, on top of another third-party one for my daughter, but that's only because it's for her. I typically am too cheap when buying things for myself (my MacBook being the sole exception ... my previous Windows laptop was $500), but I may now consider doing the same for myself. If I learn anything new, I will report here.

Sorry this is so long.

Update:   Lately, had a few phone sessions with Apple Support. 1st recommendation was to update to Big Sur 11.6.2 from 11.6.1.  After the update, the wifi random drops ( approx 3-4/day) continued and then it started experiencing kernel panic restarts after long sleep.  

Next Apple support session, a couple of days later, was recommended to upgrade to Monterey 12.1.   After installing Monterey update, it's been 4 days without any wifi drops or internet disconnects. Also, no more kernel panics.  

So, for now, it's looking like the Monterey upgrade did the trick. 

I was having the issue with frequent (every 5-10 minutes) WiFi disconnections on my M1 MBP running Monterey 12.1. This happened both at home and at work, both quite low-interference WiFi environments. What fixed it for me was disabling the awdl0 interface by entering this command in Terminal:

sudo ifconfig awdl0 down

Beware that this will disable AirDrop, at least until next reboot. (You can re-enable the awdl0 interface by changing the word "down" to "up" in the command.)

I had a similar issue with a brand new MBK and called Apple Support. We troubleshooted this as good as possible without having Wifi. After an hour they decided that the unit was defect. I got a box next day to ship the unit for repair. A week later it arrived back with a changed motherboard and it works since.

It seems Apple stands behind their products.

tianwg--

From your description, your display adapter is creating interference in the Wi-Fi band that is messing up your Wi-Fi signal.

Why do I have difficulty with Wi-Fi or Bluetooth devices when USB 3 devices are attached to my computer?

Some USB 3 devices can generate radio frequency interference that can cause Wi-Fi and Bluetooth devices operating in the 2.4GHz band to have issues communicating with your computer. Here are some tips to avoid this issue:

• If your USB device has a cable long enough that you can move the device, place it away from your Mac—and make sure not to place it behind your Mac, or near the hinge of its display. The antennas for Wi-Fi and Bluetooth are located there, and USB 3 devices placed there might interfere with your wireless connections.

• If you're using adapters or dongles on a Mac computer with Thunderbolt 3 (USB-C) ports, plug them into the front port on the left side of your Mac, or into the ports on the right side (if your computer has them). These ports are the farthest away from the antennas, making interference less likely.

• To avoid interference on the 2.4GHz band using Wi-Fi, try using the 5GHz band instead. You can change this on your wireless base station. Bluetooth always uses 2.4GHz, so this alternative isn't available for Bluetooth.

from:

About USB on Mac computers - Apple Support

Resolve Wi-Fi and Bluetooth issues caused by wireless interference

https://support.apple.com/en-us/HT201542

One item sometimes overlooked is setting

System Preferences > Network > Wi-Fi > (advanced) >TCP/IP > IPv6 ... to Link-local only.

More modern equipment may be trying to use IPv6 to make Internet connections if you do not do this.

Power Interference? My laptop was constantly dropping wifi, no apps being used only chrome for browsing. I unplugged the power adaptor from the Left-hand side and the issue vanished. I will need to test it further with it plugged into the right-hand side to see if it re-occurs. If not it is a quick and easy workaround, but not a great design.

There is an acknowledged problem with Wi-Fi using the 5GHz band on M1 Macs. It appears that the software does not deal well with a split high band 80 GHz channel. When loading gets heavy, it stops working properly.

One User reported that changing the Router settings to 40 MHz channel on 5GHz solved their problem.

Normally, I would recommend that you get an Ethernet adapter. But at the moment, all the aftermarket ones are using an RTL chip that has a different problem, but similar symptoms -- stops working under heavy loads. We think the belkin adapter sold in the Mac store works, but this has not been confirmed.

Both of these issues should be fixed in updates coming soon.

For everyone experiencing Wifi issues with M1 devices I've done more testing and am pretty sure I've narrowed down the problem, although I don't know if the problem is Apple Hardware or Software. Here's my situation. I have many Apple devices in my home as well as +20 other smart devices that access my wifi 24x7. All of those devices work fine, except for my M1 Apple Devices. Even my Apple devices that are not M1 work perfectly fine so the problem is with M1 Apple Devices.

My M1 devices are 1 MacBook Air, 1 Mac Mini and 1 iPad Pro. The 2 Mac's constantly drop Wifi connectivity throughout the day making them very frustrating to use and the iPad Pro drops connectivity occasionally (sometimes days between it happening). What happens is you can be browsing the web, watching a youtube video or the device can be doing a time machine backup and out of nowhere the Wifi signal drops. When in the browser you simply get a spinning wheel or the page won't reload and after a minute or two it'll say something like You no longer have internet connectivity. If in Youtube it'll take you to a reload page screen where clicking on the icon never gets it working. The only way to recover is to turn Wifi off and back on again, or reboot, or something you an put the device to sleep and wake it back up and it'll reconnect.

My home wifi is provided by Xfinity (Comcast) and they provide my router with is the new/latest Xfi router. After doing extensive testing what I've noticed is when these M1 devices (especially the Macs) are close to the router the acquire the 5Ghz network and lock onto an 80Mhz channel of spectrum. When they do this they constantly drop from Wifi. On a Mac the way to see wifi connection settings is by holding down the Option Key and clicking on the Wifi icon in the upper right part of the screen.

When I turn off the 5Ghz network so my M1 Macs only connect to the 2.4Ghz network the connection stays up and works fine. I came across a post from someone I believe on Redit that said the 5Ghz 80Mhz channel bandwidth is a known issue with these M1 Macs but I don't think it it cause I've had my M1 devices for months and there have been several software updates and Apple has done nothing to fix this. Assuming it can be fixed with Software.

In that same Reddit thread I mentioned, it said if you change your 5Ghz router settings to a Channel Bandwidth of less than 80 (options are typically 40/20 or just 20), they said that worked for them. Unfortunately for me Xfinity locks down the settings in the router where I can see the options to do this but they won't let me make the changes to test it. I called their support line and they did something to try and change that but the router still won't let me make changes.

If anyone else is having this problem and it's with a M1 Mac, do what I'm suggesting above to see what Wifi network your Mac is connected to when having this problem and post your settings here. If we can see that everyone having this issue is on 5Ghz 80 Channel Bandwidth, then I think it's pretty certain the M1 Macs have issues using those Wifi routers that offer this capability. BTW, for those who are not technical 5Ghz and 80 Channel Bandwidth offers much higher Wifi speeds for devices that can connect to it and have a high bandwidth internet provider plan. So for anyone that says, just use the 2.4 Ghz wifi my response to that is sure if you want a slow congested connection it's fine to use 2.4Ghz. But if you want to take advantage of the internet plan you're paying for from your ISP, you definitely want your Macs to work on the 5Ghz high channel bandwidth settings.

Here's a screenshot of what the Wifi connectivity options look like and what field of data let's you see which network (2.4 or 5Gzh) and the Channel Bandwidth your Mac is connected to.

I am absolutely baffled as to why this works. (It worked for me too, after days - nay, weeks - of pulling my hair trying to figure out why I could get 950/950mbps over ethernet, while WiFi would show a Tx rate of 866mbps, yet once I started doing anything with continuous bandwidth over WiFi, it would throttle down to approximately 20mbps/100mbps.

Network Setup:

1. AT&T Gig Fiber FTTH -> ONT
2. ER-X with eap_proxy
3. BGW-210 (cert auth only, not used for net connection)
4. Netgear JGS524PE 24-port switch w/PoE
5. UAP-AC-LR (max concurrent throughput is around 300mbps)

Hardwire Setup: MBP13 M1 2020, 256GB SSD, 16GB RAM (Network "stuff" installed: Little Snitch, Proton VPN)

• Caldigit TS3+ Ethernet connection -- using original TB3 0.5m cable that came with the TS3+
• GS105e Ethernet Switch
• CAT5e Ethernet to JGS524PE switch (see above for remaining connections)

Wireless Setup:

• MBP13 M1 connected via WiFi 802.11ac 5G, specified channel, 80MHz width

The Fix

I tried many things, including uninstalling Little Snitch and its system extension(s), deleting ProtonVPN, deleting all network preferences, changing power settings on the AP, etc.

Then I unchecked "Auto-join" for all networks except the SSID in the house I connect to primarily, and I'm back up to 280/280mbps connection over WiFi. To get all the way to the max speed the AP supports, I disabled Bluetooth, and I got ~310/300mbps.

I would really like to know what changes those checkboxes does in terms of the way the MBP's antennas listen for / send WiFi signals, because that seemed to completely cure my WiFi throttling issues. Maybe if you are set to Auto-join two networks that your Mac can see at the same time, the implementation of WiFi connections on the M1 Macs doesn't handle that very well? I thought my problem was the 80MHz channel overlap mentioned previously on this thread, but I didn't even have to switch down to a 40MHz channel for this fix to work. Can't explain that! (😂)

TL;DR - Uncheck all the Auto-Join boxes in your WiFi 'Preferred Networks' section, and that seemed to fix the problem for me.

This is maybe marginally useful...

We bought my mother-in-law an M1 macbook air for Christmas, and it was delivered yesterday. I brought it into work, connected it to the campus wireless, and it was rock solid. Downloaded and applied the 12.1 update (it was at 12.0.1) with wireless diagnostics running the whole time and didn't get the slightest hiccup.

That is another data point to suggest that this is some sort of manufacturing defect that comes in certain batches of computers but not most of them. There are several people on this thread who have already reported that when Apple replaced some hardware on their machine or even the whole machine then the problem went away. And there is my experience, which is that I've got two freshman girls with otherwise identical MBPs, and one has no problems and the other one won't stay on the campus network, with the one that won't stay on the campus network having no problems with home networks.

802.11n is adequate for many uses. Your observation that it could be better with a better Router that supports 802.11ac is certainly true, but in my opinion, that is "fine tuning" to be addressed later once the GROSS issues being reported are made a bit better.

RSSI

A quick reasonableness-check is looking at raw signal strength, (reported as RSSI) in the snapshot available by holding the Option key while clicking the Wi-Fi icon in the menubar:

here are some reference numbers:

• Right next to your Router, you should be seeing RSSI numbers around -50 or slightly better (closer to Zero, so -40 is better still)

• if the signal level declines below RSSI of -70 (or larger negative numbers, so -80 is worse), your Mac will get ready to switch to ANY better network, if another network is available. So -70 indicates miserable signal strength.

• Apple guidance tells system admins to try to overlap cells in a multi access-point setup to get at least -65 at every location, or your network simply will not be reliable enough.

wait, how do you have TWO with same SSID on channel 48? and two on channel 9?

That is NOT OK If they have any opportunity to overlap (as they clearly do from where you are sitting).

You should have different access points on DIFFERENT channels, to reduce interference between your own access points. Contrary to what you may have read, two on same channel does NOT improve switching time in the slightest -- it merely produces self-inflicted interference at all times.

You are using channel 6 in the very crowded and interference-prone 2.4GHz band. Your RSSI (Raw Signal) of -72 is TERRIBLE.

Within a few meters of your Router (straight line-of-sight with no walls in between) your signal should be stronger than that.

To test whether your antennas are broken, place you computer within a meter or so of your Router.

If your RSSI is not between -50 and zero, your Hardware is broken or your antennas disconnected.

My house is solid masonry construction, and the signal falls off very rapidly because the signals do not go through masonry. I am now up to FOUR Wired Routers at once to get "pretty good" coverage of my home.

Just a brief update: I was able to fix the issue without any complication. For my computer connection, the problem was a mixture between using a VPN in my school network (I use Windscribe), and that the Key chain access certificates of my school network weren't up-to-date (for some reason that I don't understand). After downloading the right certificates and turning off the VPN everything worked perfectly.

The thing with the VPN is strange though, sometimes I connect to it for work and the internet works without problem, but after a while it gets disconnected again. Once I turn off the VPN it works normal again. Idk, maybe something with the VPN itself?

My advise for people who is struggling with this is first try to go to a public network and see if the problem persists. If not, then maybe the issue is in the certificates and how the M1 keeps them up-to-date.