I have the same problem.
Whats 'brickwall" about it ? If I adjust a peak limit of -1db, it still goes over +1.5.
I have to set it at -3db or so to keep it under -1.0
(And yes, its placed under the green line)
Looking at the brickwall limiter, the max peak does not exceed the setting. but at the same time the loudness meter indicates that the said setting is exceeded
Is it possible that the loudness meter is not reliable?