Your rule is fine if you do not mind copying the whole folder every single time something changes. If you do it this way, it is not necessary to copy the folder structure since you are copying the whole folder.
My suggestion to make it work better is to have it go into subfolders (the subfolder rule) and then have a rule to copy each file, using the folder structure option while doing so. You would need to limit the folders it goes into in the first rule to prevent that particular folder from being copied.
Looking at it again, though, maybe it's best to use the sync rule I linked to back at the beginning. Have Hazel monitor folder A and then add a condition to the rule to filter out the "sounds" folder. Note that it will also sync anything else added to folder A. Not sure if this is what you want but if not, you'll have to change the rule to not sync that stuff.