Ah. My bad. That's kind of covered indirectly within the third reference paper (https://www.sciencedirect.com/science/article/abs/pii/S0959438808000871) and more-so in this paper: https://pmc.ncbi.nlm.nih.gov/articles/PMC2724262

Part of the process for our hearing involves otoacoustic emission (wikipedia), i.e., creating sound. My arm-chair understanding is that we think this part of the process misbehaving is a main contributor for objective tinnitus and why we can record it under the right circumstances.

tl;dr: ear too loud.