picked up a used phantom 4 pro plus controller. can't seem to find any documentation anywhere online on how to use it. anybody have a link they could share on how to use all of the functions. Also when I turn on the controller or hit the RTH button it does not beep to let me know its returning to home or that the controller is activated. power lights all work fine just no beep indicator. is there a way to turn this on or off? thanks in advance!