I always power up the multi panel after I’ve started the sim (I use a powered usb hub so equivalent is plug in usb direct). It never works if I power it up before launching. Might help.
Yes, this is a known issue. If you have the Switch Panel from us then turning on the Avionics Master will wake it up, otherwise you need to assign Avionics Master 1 to a button on your controller or somewhere on the keyboard and then pressing that will wake the Multi Panel up.