Ron Natalie wrote:

Even engine noises are frequently enhanced by ANR. I kept hearing
a clanking noise in the ANR. I pulled off my headphones for a "better
listen" and couldn't hear it. With the ANR I heard it. On landing
I found my exhaust pipe had busted a weld and was flapping around.

I was able to hear a starter that was stuck engaged WITH the ANR set on.
The sound was not audible by my companion pilot with a non-ANR set, or
me with the headset removed.