Does the table have any sort of covering on it that might have loose fibres that get sucked into the air intake of the cooling vent? It could even be simple dust build up. Get yourself one of those compressed air cans and give it a good blow through, so to speak.
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Do you know that we're all in line for succession to the throne? Really?
Well, if forty-eight million, two hundred thousand, seven hundred and one people died I'd be Queen.