20 points to the person who knows the answer.
Something very strange has just occurred and I am in need of explanations...
I was making myself a cup of tea this evening 'cause it's cold and rainy out, and tea is just the beverage for such a night. As I added the milk, my mug began to whistle at me. A very strange, high-pitched, whiny whistle. I feared for the safety of my mug (was the tea too hot? Was my mug about to crack? Even though I first tempered it with hot tap water?) so I quickly transferred the whistling drink to another mug. As I was pouring the tea into the new mug, the whistling increased in pitch steadily, until it ceased altogether. Hm.
Upon examination of the whistling mug, I found no cracks of any kind... nothing out of the ordinary at all... nothing different from the last time I drank tea (quiet tea) from it. So, as an experiment, I transferred the tea back to the whistling mug, where it promptly began to serenade me again. Puzzled and cold, I transferred the tea back to the quiet mug, and went about my business.
But it's still bugging me...
Does anyone have any ideas as to the source of the whistling? Help put a sorely anal retentive mind at ease. Please.