Godmorning :)
To set the option to '1' on your beomaster 6500 via beo4:
1. press powerbutton while you press list button, and the display say's ADD?
2. press LIST until the display say's OPTION?
2. press OK, then V.OPT blinks ind the display
3. press LIST until the display says A.OPT
4. press the button '1' for option 1 while pointing your beomaster 6500, the red diode on your beomaster reply's you with one blink :)
Thats it, you are done...