"Do all the Fusion supermarkets in Hong Kong play the same music and is it just the one melody?" my friend F asks, apropos of nothing, as we hurtle past the Eiffel Tower, the pyramids of Giza and St Mark's Square.
I have asked myself the same question, more than once.
"And can you hum it?" he continues. Unfortunately, I can. Because the two Fusions I visit regularly, in Mui Wo and Tung Chung, play the same melody day and night, on a never-ending loop.
It must be the monorail thing on which we are cruising at a leisurely speed at tree-canopy height around Window of the World in Shenzhen that has made F think of Fusion's muzak.
This theme park, charging a hefty 180 yuan (HK$218) admittance, takes you around the world, past Hawaiian huts, Mount Rushmore and (inexplicably) dinosaurs that are roaring - despite scientists saying they lacked the necessary vocal chords to do so - in about an hour-and-a-half's brisk walk.
It's the third theme park F and I have visited in Shenzhen this year, the other two being the rusting hulk of a Soviet aircraft carrier at Minsk World and the wondrous celebration of dancing and colourful ethnic minorities that is Splendid China.
We hoped Window of the World (not "on" or "to") would resemble the latter; well thought out, well laid out and really well done. But it seems the owners ran out of steam after finishing the Korean and Japanese imperial palaces; Mount Fuji, for example, looks like a heap of grey cement that has been dropped from a height. There isn't even a snowcap. Tsk tsk.
If it hadn't said "Fuji" on the more or less unreadable map - on which the only recognisable drawings are of windmills and the Eiffel Tower - I would have guessed it was Manila's infamous rubbish heap, Smokey Mountain.
For me, a highlight is a middle-aged staff member in a baseball cap slumped between the humps of a phlegmatic yet haughty-looking camel, with the tip of a gold-painted pyramid rearing up behind them.
Another interesting feature are the carp thrashing frantically away amid the unexpected bamboo forest of the Grand Canyon, a heap of cement painted a rusty monobrown.
Feeding frenzied carp, I'd say, is one of the most fun things you can do in Window of the World. Another is going on the romantic swing built for two. But perhaps the best for me is watching F cringe as I give a - I have to say - pitch-perfect rendition of the song they play on a never-ending loop in Hong Kong's Fusion supermarkets.