I think we talked about this before but I have found that if you a) Use the PEQ and b) have any
channel gains above +7dB the ADA Signal clips and you get no output.
As you say this only happens at high-ish levels (-15dB to -10dB) and during action scenes, especially deep bass. I first noticed this during Underworld Awakening in the car park battle at the end of the movie.
On my setup I only used PEQ cuts on the bass channel but some of the other channels have some +3dB boosts in places.
What I can say for sure is:
1. If I turned the PEQ off the cut-outs stopped.
2. If I lowered all the channel levels so they do not exceed 0dB the cut-outs stopped.
I am guessing there is either some kind of signal level limiter or signal clipping going on but I believe it is set too low. You can get round it as I mentioned by setting the channel levels lower but the downside is the volume dial doesn't read true so you need to turn the volume up higher.