Update FAQ.md

Author: morrownr

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@@ -1 +1,58 @@
+Frequently Asked Questions (FAQ)
 
+Question: I am having problems with my Alfa AXML or Alfa AXM or Comfast CF-953AX. The wifi is not working. It seems to crash when coming up. What can I do?
+
+Answer: This is a known problem that started in early 2024 around the time kernel 6.7 was released. There have been unsuccessful attempts to fix this problem. It is a strange problem in that it seems that bluetooth is involved. Most adapters with the mt7921au chipset do not have this problem. The 3 adapters listed in the question are the only 3 known to have this problem so it appears that something specific to these 3 adapters is causing the problem. Right now all that can be offered is a workaround.
+
+This workaround was posted by @ZerBea :
+
+Use one of the following Linux kernels:
+
+$ uname -r
+6.6.x
+
+or
+
+$ uname -r
+6.12.x
+
+Make sure you're running latest WiFi firmware:
+[18615.766176] mt7921u 1-9.3:1.3: WM Firmware Version: ____010000, Build Time: 20241106151045
+
+Disable BT stack:
+echo "install btusb /bin/false" >> /etc/modprobe.d/local-dontload.conf
+
+reboot or unload btusb
+
+connect the AXML to an USB2 port or a USB2 hub
+
+Now dmesg should print this:
+
+[20844.686881] usb 1-9.3: new high-speed USB device number 12 using xhci_hcd
+[20844.818337] usb 1-9.3: New USB device found, idVendor=0e8d, idProduct=7961, bcdDevice= 1.00
+[20844.818343] usb 1-9.3: New USB device strings: Mfr=6, Product=7, SerialNumber=8
+[20844.818346] usb 1-9.3: Product: Wireless_Device
+[20844.818347] usb 1-9.3: Manufacturer: MediaTek Inc.
+[20844.818349] usb 1-9.3: SerialNumber: 000000000
+[20845.018645] usb 1-9.3: reset high-speed USB device number 12 using xhci_hcd
+[20845.159101] mt7921u 1-9.3:1.3: HW/SW Version: 0x8a108a10, Build Time: 20241106151007a
+
+[20845.420854] mt7921u 1-9.3:1.3: WM Firmware Version: ____010000, Build Time: 20241106151045
+[20847.020857] mt7921u 1-9.3:1.3 wlp22s0f0u9u3i3: renamed from wlan0
+test monitor mode and packet injection:
+
+$ sudo hcxdumptool --rcascan=active --tot=1 -c 1a
+...
+^C
+132 Packet(s) captured by kernel
+0 Packet(s) dropped by kernel
+57 PROBERESPONSE(s) captured
+
+exit on sigterm
+
+$ sudo dmesg
+
+[21146.046337] mt7921u 1-9.3:1.3 wlp22s0f0u9u3i3: entered promiscuous mode
+[21153.630136] mt7921u 1-9.3:1.3 wlp22s0f0u9u3i3: left promiscuous mode
+
+Monitor mode (device entered promiscuous mode) and packet injection (57 PROBERESPONSE(s) captured) is working!