docs: Update pairing instruction to mitigate stability issues

See-also: #198
Signed-off-by: Kai Krakow <kai@kaishome.de>

docs/README.md

@@ -197,9 +197,10 @@ Please feel free to add other Distributions as well!
 * wait until all available devices are listed (otherwise it may be hard to identify which one is the gamepad)
 * push the connect button on upper side of the gamepad, and hold it down until the light starts flashing fast
 * wait for the gamepad to show up in bluetoothctl, remember the <MAC> address (e.g. `C8:3F:26:XX:XX:XX`)
+* `[bluetooth]# scan off` to stop scanning as it may interfere with properly pairing the controller
 * `[bluetooth]# pair <MAC>`
 * `[bluetooth]# trust <MAC>`
-* `[bluetooth]# connect <MAC>`
+* `[bluetooth]# connect <MAC>` (should usually not be needed but there are [open bugs](https://github.com/atar-axis/xpadneo/issues/198))
 * The `<MAC>` parameter is optional if the command line already shows the controller name
 
 You know that everything works fine when you feel the gamepad rumble ;)