You probably have AOV - Acoustically Optimised Venting. It haven't worked well in my case, because it made an assumption that I will be susceptible to occlusion effect, which in reality isn't a problem in my case. So I was underfitted in higher frequencies in my case.
AOV is simply more for giving comfort at the expense of audibility. Perhaps with your flat loss it is working better.
If you are going to make a new cShell in the future, try with the UP receiver it will give you more access to high frequencies, which are crucial for understanding in noise and can provide more accurate peaks of speech in noise whichbis also useful to boost speech understanding in that condition.
Here are articles, why more powerful receivers may be more effective in noisy conditions:
You’re ignoring this member’s posts.