| thanks for your responses guys,
I look into the de-burring route - seems like a lot of hassle that should been addressed by the manufacturer - but then again the price was pretty good.
I am gathering some interesting feedback from the various boards I have posted the question.
Seems like the buzzing is common, but not inevitable.
If I get a definitive answer I will tack it into this thread for anyone who is interested.
BTW - the supplier of the discs says that he is sending me a set of replacement discs immediately - if this is the case, I am impressed with his service and I will post his details here when I receive them.
Spin | 
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