I have (2) Multiplus compact 2000 units in split-phase configuration and "switched as group" is unchecked. I can only get the Mulitplus on line 1 to work with "ignore AC" and successfully switch over to AC when the load is above the set limit. The other Multiplus will always ignore the AC and never connect even when the load is beyond the set limit. Both inverters have the exact same settings. What am I doing wrong?