Tok Tok Tok...? Sounds funny, but I guess there thousands reasons out there that can cause such an annoying sound but seriously dont believe it could be "manufacturer" issue it can also be a foreign object... little stone, loose nut,.. etc why cant you open up the tail blow in a jet of air?

For the sound to be coming and going sometimes simply means something must be either loose or a free object thats start roaming when not entangled.

But if you really think its a phantom... hmn... well... just blow a Vuvuzela behind your car 7 times and screem "I say come out!" then blow another 3 times leave the car for the night... while going inside your house dont look back till the following day!

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