Bad 5 GHz wifi on new 16" MBP 2023

[stanft]

Hi everyone,

I am experiencing some WiFi connection problems on my new 16" MBP 2023. I have started some investigations using the WiFi diagnostic tools, and what I have found out is that my old 16" MBP 2019 has a better WiFi connection by far compare to the new MacBook Pro.

Both MacBooks are located next to each other. Both are connected to the same 5 GHz WiFi. I measured signal strength and noise and swapped the positions - the values remain the same. Even if I shut down one of the machines there is no change in the values.

Below I have attached two screenshots of the WiFi signal diagnostic. This is the 16" MBP 2023:

And this is the 16" MBP 2019:

As you can see the MBP 2019 has a tx rate that ranges between 350 and 530 Mbit/s while the MBP 2023 only has 30 - 250 Mbit/s roundabout. The main difference seems to be the noise on both machines (in German "Störsignal"). The signal strength is nearly equal for both but the noise on the MBP 2019 is around -95 dBm while the noise on the MBP 2023 is around -82 dBm.

I have simply no clue what is going on here. Could the higher noise on the MBP 2023 be a specific hardware problem of my machine (which I hope it is not)? Or is this a common finding because of the different hardware architecture of both machines.

Maybe somebody else here has some ideas on this or has experienced the same...

Best regards,
Stephan

 

[appltech]

Hi!
Have you tried to check/disable Bluetooth, DNS , proxy and network Sharing (on the Mac)?
Faced with a problem when Wifi (Mac utilized 5Ghz) was disconnecting and unstable when something/somebody was moving in/out specific zone. Disabled the abovementioned, restarted the Mac -- problem was gone. Maybe, in your case it could be also helpful.

Thinking of which, on the gateway side there isn't madness when 2.4 is under IPv4 and 5 at IPv6? I saw that once

 

[stanft]

Have you tried to check/disable Bluetooth, DNS , proxy and network Sharing (on the Mac)?

I haven't tried that but thanks for the hint.

I just disabled the auto channel selection on my router and set another channel manually (from 36 to 132), and this has changed the signal on the MBP 2023 to the better. Noise is now around -89 dBm (the MBP 2019 is around -95 dBm).

But I'm still asking myself why the new MBP has such a worse signal quality compared to the old MBP in the same environment.

 

[appltech]

I haven't tried that but thanks for the hint.

I just disabled the auto channel selection on my router and set another channel manually (from 36 to 132), and this has changed the signal on the MBP 2023 to the better. Noise is now around -89 dBm (the MBP 2019 is around -95 dBm).

But I'm still asking myself why the new MBP has such a worse signal quality compared to the old MBP in the same environment.

There could be a heck how many reasons starting from different suppliers and contractors so parts can differ (something similar to the memory chips variety in GPU's), FireWall that goes crazy, background service(s) that take priority

 

[stanft]

I think I may have found a reason for the noise: I just found out that the MBP 2019 connects with 80 MHz bandwidth while the MBP 2023 connects with 160 MHz bandwidth - which is great because of higher Tx rates but not so great because of the higher noise :-(

Unfortunately, my router does not support a limitation to 80 MHz. And I have found no way in macOS to force the WiFi connection to a max 80 MHz bandwidth. This is a pity because at my house the 160 MHz bandwidth seems to be worse than 80 MHz because of the higher noise.

 

[stanft]

I am still in the ongoing process of testing different WiFi constellations. So far I have found out that in general when using a 5 GHz network the new MBP 2023 has a substantial (10 dBm) higher noise compared to the older MBP 2019.

On a 2.4 GHz network the noise level is nearly the same on both machines.

Is anybody here who has the chance of comparing a 2019 or older MBP to a MBP 2023 on a 5 GHz network in terms of noise? Maybe the noise difference is just the way the new WiFi module is built. That would be great news indeed because then I don't have to worry of having a hardware problem on the new machine.

Best regards,
Stephan

 

[FNH15]

Just a thought - the Intel MBPs are 3x3 MIMO, the Mx Macs are all 2x2 MIMO.
Probably why you’re seeing a lower Tx rate on Wifi 5 (and lower signal strength).

 

[stanft]

Just a thought - the Intel MBPs are 3x3 MIMO, the Mx Macs are all 2x2 MIMO.
Probably why you’re seeing a lower Tx rate on Wifi 5 (and lower signal strength).

Yes, I already found that information. Anyhow, my finding is not the signal strength (which is nearly equal on both machines) but the much higher noise level the MBP 2023 has.

I just found out something maybe interesting: If I look at the WiFi signal details with Option+Click on the WiFi symbol the MBP 2019 shows around -95 dBm noise all the time. On the MBP 2023 the noise level is around -85 dBm. But: If I switch the network on the MBP 2023, the noise level goes down to -95 dBm for about five seconds - and then raises up to -85 dBm again. And this happens every time I switch the wireless network. The MBP 2019 does not show this behavior.

 

[iMacDragon]

-85 is better than -95, closer to 0 the better.

I suspect the graph may be due to move aggressive power saving.

Have you done any actual comparisons of real transfers, e.g. seeing if the graph remains higher if actively sending a lot of data? If it doesn't remain flatter then, then there probably is some issue.

And indeed, the 260 vs 390 sounds like mimo difference of 2x 130 vs 3x 130

 

[stanft]

-85 is better than -95, closer to 0 the better.

That is true for the signal. But I am talking about -85 dBm noise. So -85 dBm is 10 dBm higher noise than -95 dBm.

Performance test is a good suggestion. I will try that today.

 

[iMacDragon]

Fair, I was thinking about the signal level not noise level.

 

[stanft]

I've made some performance tests. It seems that the fluctuations in bandwidth are indeed a result of some kind of energy saving. As soon as there is traffic on the WiFi connection the bandwidth keeps nearly constant at the max level (260 Mbit vs. 390 Mbit).

Speedwise I cannot measure any difference between the MBP 2019 and the MBP 2023 because my internet connection simply is not fast enough. Both machines have no problems to reach the max bandwidth of my internet connection (around 80 to 100 Mbit downstream).

In fact, it seems that the WiFi details shown by macOS are a bit weird. For example: I swapped the location of both machines. The MBP 2019 previously maxed out at 390 Mbit. On the new location it maxed out at 260 Mbit - as the MBP 2023 previously does. The MBP 2023 itself now supports up to 390 Mbit on the new location - like the MBP 2019 before. BUT: The old MBP 2019 still has three streams even though the bandwidth is less. And the MBP 2023 only has one stream but supports 390 Mbit.

 

[dmccloud]

I think I may have found a reason for the noise: I just found out that the MBP 2019 connects with 80 MHz bandwidth while the MBP 2023 connects with 160 MHz bandwidth - which is great because of higher Tx rates but not so great because of the higher noise :-(

Unfortunately, my router does not support a limitation to 80 MHz. And I have found no way in macOS to force the WiFi connection to a max 80 MHz bandwidth. This is a pity because at my house the 160 MHz bandwidth seems to be worse than 80 MHz because of the higher noise.

The 2023 14" and 16" MBP both have WiFi 6E, which adds that 160 MHz band on top of the existing 5Ghz and 2.4 GHz bands used with WiFi 6. What I have found is that despite my router only supporting WiFi 6, the Mac's throughput from the same room as my gaming desktop is around 35-40% higher than said PC.

 

[stanft]

The 2023 14" and 16" MBP both have WiFi 6E, which adds that 160 MHz band on top of the existing 5Ghz and 2.4 GHz bands used with WiFi 6. What I have found is that despite my router only supporting WiFi 6, the Mac's throughput from the same room as my gaming desktop is around 35-40% higher than said PC.

But did you have a look on the noise level of your desktop and the MBP. Are both having the same noise level - or is there a significant difference? I am simply asking myself why the new MBP 2023 has 10 dBm more noise on the same location with the same WiFi network/channel etc.

 

[dmccloud]

But did you have a look on the noise level of your desktop and the MBP. Are both having the same noise level - or is there a significant difference? I am simply asking myself why the new MBP 2023 has 10 dBm more noise on the same location with the same WiFi network/channel etc.

I don't care about the noise level because the Mac's WiFi is significantly faster on the same network. I'm pulling 800-900 MBps on a gigabit connection, so I'm not complaining in the least...