I have an older SMA Sunny Boy I would like to AC couple to my Multlplus however the Venus does not recognize it as its latest available firmware ( V2.80 ) does not meet the criteria of V 2.81 ( https://www.victronenergy.com/live/ccgx:ccgx_sma ) . It obviously does not appear on the Venus or VRM but can I still use it in AC coupled mode with the Multi controlling power via frequency shifting?