Ubuntu 22.04 WiFi Only Connecting at 72Mb/s

[anspectrum]

My laptop WiFi had no issue to connect at higher speeds in the past. Yesterday, I just checked while connecting to 802.11ac Access Point that laptop is not connecting higher than 72Mb/s. There is no problem with Access Point since my mobile is also connected to same AP with 433Mb/s. I suspect that in past when Ubuntu updated its kernel that resulted in breaking some WiFi features. Please suggest where I can look for to try fixing it.

lspci output

05:00.0 Network controller: Intel Corporation Dual Band Wireless-AC 3165 Plus Bluetooth (rev 99)

inxi output

System:
  Host: OS Kernel: 5.15.0-73-generic x86_64 bits: 64 compiler: gcc v: 11.3.0
    Desktop: MATE 1.26.0 Distro: Ubuntu 22.04.2 LTS (Jammy Jellyfish)
Machine:
  Type: Laptop System: LENOVO product: 20KN0002AD v: ThinkPad E480
    serial: <superuser required>
  Mobo: LENOVO model: 20KN0002AD v: SDK0J40697 WIN
    serial: <superuser required> UEFI-[Legacy]: LENOVO v: R0PET35W (1.12 )
    date: 01/22/2018
Battery:
  ID-1: BAT0 charge: 39.4 Wh (94.3%) condition: 41.8/45.3 Wh (92.3%)
    volts: 12.4 min: 11.1 model: SMP 01AV446 status: Charging
CPU:
  Info: quad core model: Intel Core i7-8550U bits: 64 type: MT MCP
    arch: Coffee Lake rev: A cache: L1: 256 KiB L2: 1024 KiB L3: 8 MiB
  Speed (MHz): avg: 800 min/max: 400/4000 cores: 1: 800 2: 800 3: 800
    4: 800 5: 800 6: 800 7: 800 8: 800 bogomips: 31999
  Flags: avx avx2 ht lm nx pae sse sse2 sse3 sse4_1 sse4_2 ssse3 vmx
Graphics:
  Device-1: Intel UHD Graphics 620 vendor: Lenovo driver: i915 v: kernel
    bus-ID: 00:02.0
  Device-2: AMD Lexa PRO [Radeon 540/540X/550/550X / RX 540X/550/550X]
    vendor: Lenovo driver: amdgpu v: kernel bus-ID: 02:00.0
  Device-3: Acer SunplusIT Integrated Camera type: USB driver: uvcvideo
    bus-ID: 1-6:3
  Display: x11 server: X.Org v: 1.21.1.4 driver: X:
    loaded: amdgpu,ati,modesetting unloaded: fbdev,vesa gpu: i915
    resolution: 1366x768~60Hz
  OpenGL: renderer: Mesa Intel UHD Graphics 620 (KBL GT2)
    v: 4.6 Mesa 22.2.5 direct render: Yes
Network:
  Device-1: Realtek RTL8111/8168/8411 PCI Express Gigabit Ethernet
    vendor: Lenovo driver: r8169 v: kernel port: c000 bus-ID: 03:00.0
  IF: enp3s0 state: down mac: 8c:16:45:38:12:d8
  Device-2: Intel Dual Band Wireless-AC 3165 Plus Bluetooth driver: iwlwifi
    v: kernel bus-ID: 05:00.0
  IF: wlp5s0 state: up mac: f8:63:3f:96:1b:c6
  Device-3: Intel Bluetooth wireless interface type: USB driver: btusb
    bus-ID: 1-5:4
  IF-ID-1: docker0 state: down mac: 02:42:5e:04:4b:98
  IF-ID-2: virbr0 state: down mac: 52:54:00:0c:81:28

iwconfig output

 IEEE 802.11  ESSID:"C511_5G"  
          Mode:Managed  Frequency:5.745 GHz  Access Point: 04:F3:52:0E:27:04   
          Bit Rate=72.2 Mb/s   Tx-Power=22 dBm   
          Retry short limit:7   RTS thr:off   Fragment thr:off
          Power Management:on
          Link Quality=60/70  Signal level=-50 dBm  
          Rx invalid nwid:0  Rx invalid crypt:0  Rx invalid frag:0
          Tx excessive retries:0  Invalid misc:33   Missed beacon:0

[jeremy31]

I don't think the iwlwifi driver likes power management being on

sudo sed -i 's/wifi.powersave = 3/wifi.powersave = 2/' /etc/NetworkManager/conf.d/default-wifi-powersave-on.conf
sudo iwconfig wlp5s0 power off

See if that works better

[anspectrum]

Earlier I had already tried that powersave option and it had not worked. This time I tried again and even restarted the laptop, speed is still 72Mb/s.

[jeremy31]

See the wireless script link in my signature and post results

[anspectrum]

Script info is uploaded here

[jeremy31]

Can you change the encryption on the 5GHz AP? It shows TKIP being used and that isn't recommended
See https://ubuntuforums.org/showthread....&#post13614520 on how to set your country code as that may help with something in the results

wlp5s0: capabilities/regulatory prevented using AP HT/VHT configuration, downgraded

[anspectrum]

Changing country code did not help. Neither changing the encryption on AP to AES. Based on following dmesg

 wlp5s0: capabilities/regulatory prevented using AP HT/VHT configuration, downgraded

Ive also tried changing channels on AP as was mentioned here but still no luck.

[jeremy31]

Run the script again and post new results

./wireless-info

[anspectrum]

Here is the new script output.

[jeremy31]

See if you can disable WPA on the router, leave WPA2 on and turn off IPv6 in Network Manager settings for the connection