Hi Going Maui - (love your screen name...I used to live in Wiehu and Wailuku!!).
For what it's worth, we had an adjoining cabin 2 years back. Our daughter and her cousin were next door...given the fact they were high school seniors (think noise factor, lol)...we didn't hear any noise, even with an adjoining room.
Another opinion...we always request the larger Concierge Class cabins with the bump out on the Sky Deck (cabin 9038 is amazing)...on all the M-class ships. This cabin is directly under the Aqua Spa Thallossotherapy solarium doors that connect to the Aqua Spa itself.
Chairs are usually arranged in the Spa area around 7-8 AM, but it never woke me up. Woke my other half up once, but it wasn't obnoxious at all...I think it must be more sound-proof than other ships? The reason I say that, last April we were in a Mini Suite on the Pacific Princess, and again were under the pool deck. My G-D it was awful!...scraping and scraping and noise...
I think you'll be fine where you are! Have a great cruise!!