I'll answer somewhat, briefly, as I am off to sleep, and will return, tomorrow if I think of further examples I can offer you.
My folks, initially, recognised that I was having trouble following directions, when I was quite young. Jumping forward a bit, I recall my Mom had described to my ASD therapist, that she had, initially wondered if I simply hadn't cared to follow directions, or, cared to do what she would request of me, or, she would give me directions for going about a task or how to play a game, etc, and I would seem quite eager, however, it would seem as if I had not been listening, or, did not find her directions necessary, or similar. She told the therapist, I showed no signs of defiance, and always seemed to want to do what had been asked of me, and I became sad, confused or frustrated when I learned I had done something incorrectly or could not complete a task. She said, I was a cooperative, content and happy child, despite the difficulties that I had been exhibiting. This was the first indiction that my parent's had, that I may have been struggling with something, or, perhaps there had been something wrong with my hearing.
When I was in first grade, I had a lot of difficulty learning to read. I was always behind and my reading comprehension suffered greatly, as the result of this learning disability, and this was when I initially went to some type of doctor, also at UCLA, and I clearly recall her telling my parents that she was surprised to see a young child complete a puzzle as quickly as me. I had to do a few different types, including a couple 3D puzzles, but, now, I am going way off topic. As I mentioned previously, I also have a separate, visual processing delay, and I read approximately 3 to 4 times slower than the average reader of my age (apparently), unless I read aloud, and, ironically, I am a visual learner and have acute visual-spacial abilities.
To answer your initial question, I have acute hearing, and I am sensitive to noise and certain sounds, but, my hyper-sensitivity to sound had not been the cause of my symptoms. It was the inability to process language, with background noise.
I would be interested to hear about your APD discovery, and the symptoms you've experienced/how it has effected you, etc. - if you'd be open to talking about it.