A lot of feedback is dependent on how you handle a disatisfied person. Did you offer a refund? On audio equipment, items shoudl be double boxed as peanuts settle and when they settle the item may shift within the box. Did you insure the package? If you had, there should have been no loss to you....Most buyers just want they item to arrive and be as described. If this person has a history of leaving bad feedback, you can check by clicking on his feedback score and seeing what he has left for others, you may have an issue you can take up with ebay. If he has no history, take it as a lesson learned and double box electronics in the future. You can always block him form bidding on your items in the future. Eventually, the comment will go way down in the stack and after 12 months, disappear...
I haven't had my coffee yet, so forgive my typing....The only question you may regret is the one you never asked!