I can't comment specifically on room 5670, but we had 5682 and 5684 back in September and LOVED our rooms. We did not hear noise from the clubs below at all. The configuration of that hallway makes for very little foot traffic. It's super close to the kid's clubs, easy access to Cabana's thanks to the aft elevator. We would book a room in this part of the Fantasy anytime! I hope this helps.
ETA - we traveled with our 5 year old son and he was not bothered by noise, location, rocking of the ship, etc. It was a great location for our family.