When an Enderman is in a boat and you make him hostile, he will try to teleport to you, however as it is stuck, it only reproduces the sound, making it seem that other enderman is chasing you.
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Playing in Minecraft Java Version 1.20. Just minding my own business playing the game and kept constantly hearing an Enderman teleporting around me, shows up in captions as well. My Enderman is also in a boat and in a glass box. He's never been angered at all before or after being placed in the boat. No matter how far I go on my island, I still hear it. Here is a video I made. As you can see on the mini map and larger map; my Enderman is the only one on the island.
Edited: I forgot to mention, the sounds are only happening during the day time. During the night there are no teleporting sounds.
Can confirm. The endermen frequently make teleport noises but can't teleport, so they end up making strange noises to try to creep out the player? I assume the intended feature is that endermen should teleport outside the boat, since using ender pearls or chorus fruit to escape a boat works.