Hi,
Before you dis-assemble the speaker, as it is 'new' was there a warranty on the product provided by the seller at all?
If there is a warranty, you don't not want to void it by opening the speaker. I suggest that you contact the seller about the problem and see what they will do to resolve it for you.
If there is no warranty on the speaker, then the best option is to open the speaker and see if you can determine what is the cause of the noise. For instance, it may be the the actual speaker cone may be loose in its housing etc.
Here is a link to the ifixit [[Topic:TDK Life on Record Trek 360]] guides which should be of some help in opening the speaker so that access can been gained to the components.
Hopefully this is of some help