The trouble is you don't know which unit is running out of headroom.
I can tell you one thing any piece of budget equipment I have ever had on the bench generally does not have enough headroom on the inputs.
This spec is never quoted and seldom measured in reviews. For any receiver preamp or mixer, it is one of the most important specs.
My last Rotel unit was very close to the wind and occasionally not adequate.
When I got my Marantz 8003 back home that was the first thing I tested, and if it had not been adequate, it would have gone back.
I was in a friends home for a week in February, and he had a Pioneer Elite receiver. I forget the model, but as far as I was concerned it was absolute junk. Every time there was louder dynamics, it had the same problem you describe. It was gritty as all get out. The Paradigm speaker system did not help, which was plain awful.
So unfortunately you are like me and probably cursed with a keen ear.