I have sceptres as well and have gotten used to wearing earplugs on longer rides. The key is to find earplugs that are comfortable to wear all day. It's true wind blast is the biggest source of noise fatigue and combined with sceptres in ANY helmet can be disconcerting on a mega milage day. Custom plugs would be the best way to go. (initial expense, but, worth it in the long run.)
Three years ago I did a 700 mile day with a beanie and no plugs and my ears were ringing for three days after. (never again!)
