tubby
From the maintenance side, we have seen this fault occasionally, usually it goes away after a couple minutes. The thinking is that simultaneous engine shutdown at the gate may trigger it, but we are getting no info from CFM or AB as to a fix. If the message is still there when I get up to the flight deck, a FADEC ground test for both channels will clear it.
Only once have I seen it for both engines. A320-NEO type.