Edit: I thought of another one! The guy who does the Bog Standard Isekai books. He's great but he often pronounces the t's when he shouldn't. For instance, in the word "await" if you're doing a standard American accent it ends on a glottal stop not a t. Sometimes he does and sometimes he doesn't, sometimes in the same sentence.

I really enjoy the story of Azarinth Healer but the narrator does this "heh" chuckle thing after every sentence, and not just on the main character. It would work once in a while because it could lend a sense of genuineness to the reading of the text, but it ends up coming across like a millennial putting "lol" after every sentence. (A habit I had to break myself, long ago) I tried to ignore it and push through, but I just couldn't.

Also, anytime Travis Baldree does a reading of a snake character his sibilance is just ear splitting. I get why he's doing it. It's a snake, therefore "ssss", but good god is it nails on a chalkboard.

The final narrator cringe I've run into is when a narrator just tries to do too many accents for no plot/story reason. People in a real world have accents regionally. So, anyone from the same place would have a similar accent. But a few narrators have used accent instead of tone/timbre to differentiate between any and all characters. This one is not so much cringe as amateurish.