Add troubleshooting step for "Not connected" problems on Raspberry Pi. (#1670)

Disabling wifi on Raspberry- and Rock Pi can greatly improve the stability
of Bluetooth.

Author: denravonska

docs/troubleshooting.rst

@@ -118,6 +118,33 @@ crash with an ``ImportError`` similar to::
 
 To fix the error, change the name of the script to something other than ``bleak.py``.
 
+----------
+Linux Bugs
+----------
+
+Occasional "Not connected" errors on Raspberry Pi
+=================================================
+
+If you are using the built in WiFi/Bluetooth module on a Raspberry Pi and and are seeing occasional
+"Not connected" errors, also manifesting as HCI error 0x3e and BlueZ error "Software caused
+connection abort", when trying to connect to a device, it may be due to wifi interference on
+the chip level.
+
+As a test the wifi interface can be disabled using either
+
+.. code-block:: shell
+
+    sudo rfkill block wlan
+
+or
+
+.. code-block:: shell
+
+    sudo nmcli radio wifi off
+
+See `this <https://github.com/project-chip/connectedhomeip/issues/16178>`_ Matter issue
+with similar problems on Raspberry Pi and other devices.
+
 ----------
 macOS Bugs
 ----------