The huge overhaul of the audio systems across the park seems to be continuing. Many new speakers that had been fitted over closed season have been connected and are working (for instance on the balcony overlooking the park when you come out of the dome, and there is now audio again on the climb up the volcano on Inferno, don't remember those speakers working for years prior).
Volume levels seem to be different in many areas every time I visit, showing they're experimenting a little to find the best levels in various places. For example the audio around Stealth's plaza and queue is so quiet at the moment it's pretty much inaudible, but Angry Birds Land and Storm Surge have had their annoying soundtracks cranked up.
Many areas (e.g. the entrance plaza, Colossus & Lost City, Swarm Island, Inferno & Jungle) that used to sound pretty meh now sound amazing.