Shriek-Shriek, Briiinng, Squawk, Cochi-Cochi, Knock-Knock-Knock-Knock.
"Honey I'm going to call the manager, I can't take the noise from the fans, air conditioner and the water pipes"
"But I turned off the fan and the air conditioner to enjoy the night, and the sounds aren't coming from the bathroom."
The noises are actually nature's night sounds that can still be heard echoing through the Caribbean evenings. Unlike big cities and more developed places, many small islands in the Caribbean still have their original night creatures, and they all breed and hunt in the dark. Yep, most of that that high pitched noise is sexy sounds of various animals, and that doesn't mean the human ones (though you might hear some of those as well)!
The single, high note that sounds incredibly shrill is most likely a Gecko, looking for a mate. They are fast, hide quickly and even slightly change colors to blend in, but the males make their calls to tell the females how to find them. This can be really loud when they are hidden in your room and the urge takes control!
Then there is the double note call that sometimes switches to a three note. In Puerto Rico they are known as cochi, the rest of the Caribbean calls them crickets, but most are tiny frogs, with a backbone in some cases of less than 9mm (1/3 inch). The males do the two note, but when the female arrives they add a third!
There are insects out there, but they aren't actually vocal, they make rasping and ringing noises, but usually with their legs rather than vocal cords! It can still be loud, but telling them to shut their mouths does little good.
The high pitched note that some people complain about and yet others don't hear are different types of bats. The Caribbean has a wide range of those flying mammals and they tend to eat everything from insects to fruits to even catching fish out of the calm waters! All are harmless and one small Mollosus bat can eat thousand of the pesky Culex mosquitoes, which is the buzzing you hear around your ears at night.
The "rolling coo" at night isn't doves, it is large toads and the sound of a dying chicken isn't a fox in the hen house, its Cuban Tree Frogs! There are also a few night birds that can get quite noisy, mainly night herons. Leave them along as they are a protected species.
What is that musical, off-key note warbling through evening air? Likely some drunk down at the bar trying to sing, the true night creatures carry a tune!