Hello,
I hope this post helps the Apple team fix the Wi-Fi issues introduced with Sequoia.
I have an Apple M3 Max MacBook Pro. I was running Sequoia 15.1 and had been experiencing intermittent internet issues, such as "Unstable Network" during Zoom calls, dropped Zoom calls, and slow YouTube streaming. I do not experience these issues before upgrading to Sequoia. I had never considered that the Mac OS would be at fault.
Yesterday I updated to Sequoia 15.2 hoping to resolve (some of) these issues. The result was the oposite. Before the update, my Wi-Fi was limping but moving. After the update, I lost Wi-Fi functionality.
Below is an image from SpeedTest.Net comparing the before (limping network: 250-400 Mbps) to the after upgrade (unstable and unreliable network), where the lowest download and upload speeds I got were 12 Mbps and 0.02 Mbps, respectively (not in image below).
To determine the origin of the issue, I tested the modem/router speed. It also uses SpeedTest.net (below) and it showed the stable and consistent download speeds of <500 Mbps I have had since forever. Spectrum's upload speeds have never been great, but I care more about downloads.
Then, to test the Wi-Fi network, I used SpeedTest.net on my iPhone 16 Pro running iOS 18.1.1, and the speeds were and still are in the >435 Mbps. I obtained similar numbers with my daughter's Chomebooks, and other family phones.
Together, these data strongly suggests that the issues are on the WiFi configuration in the Sequoia operating system. I searched on Google for potential solutions discussed by other Mac owners, and some things helped, other maybe helped, and most did not matter.
Things that helped:
- Forget the Wi-Fi and use a wired connection instead - HELPED
- Turn off the "Apple Network Firewall"
- Turning off the "Apple Network Firewall" is absolutely required if you want to use a VPN with a wired connection. If you do not plan to use a VPN, you can leave the "Apple Network Firewall" on
- Turning off the "Apple Network Firewall" significantly hepled Wi-Fi functionality
Things that might have helped:
- Turning off the VPN
- Turning off iCloud "Private relay"
- NOTE: in a wired connection without Firewall and with VPN, turning on the "Private relay" has minimal impact on speed
- The "Limit IP address tracking" toggle switch
- Adding the 8.8.8.8, 8.8.4.4, 1.1.1.1, 1.0.0.1 DNS servers
- NOTE: in the wired connection I am still using the DNS server from my router/modem, which I am getting automatically from Spectrum; so it is very unlikely that addidng these DNS servers had major impact
- Changing the Wi-Fi MTU from standard/auto (1,500) to 1,453
- Disabling "20/40 MHz Coexistence" in my modem/router
Things that did not matter:
- Uninstalling Sophos antivirus to remove content filters, but it dod not have any impact, so I reinstalled it
- Rebooting the router/modem
- Forgetting the network and re-signing in
- Cleaning the DNS cache
- Using a fixed IP address
- Changing the channels for 2.4GHz and 5GHz
- Renewing the DHCP lease
- Deleting the files below from the /Library/Preferences/SystemConfiguration folder and rebooted the Mac
- Rebooting the computer as follows
- Simultaneously pressing shift + ctrl + cmd + ON_button for 10 seconds
- Pressing the ON_button imediately followed by simultaneously pressing option + cmd + P + R
The final diagnostic run by the Wireless Diagnostic app is below.
Please let me know if there is anything esle you may need to unravel this problem to fix it ASAP, as many of us rely on Wi-Fi for our day-to-day work.
Thank you.
All the best,
Andres
