I am in a bunker in Hollowed Moor. As you enter there is a lot of Ore and then a small portal you have to fire up. Once in, there is a short path before you begin to hear those familiar sounds, the ones you have to hit in order.
Shortly ahead there is that platform where you will eventually get your essence. Close by on your right are two, one surrounded by bars so you have to move around them, and a third one floor above and to your left.
Usually they sound at a particular pace. The three I can find do not. That gives me the strong impression that there are quite a few more I am NOT seeing but unless I am missing a pathway, they are not here. Hints, please.
#Hollowed moor Bunker
vernal rune
OK, so they no longer keep to a specific rythem.
tawny cliff
Actually they do. The ones in these bunkers are still tied to the pre 0.5 "pace" and go quite slowly. The regular POI out in the realms were tweaked to activate the sounds faster.
clever estuary
Also, just a small tip of 'if you didn't know': You can shoot those to activate them, rather than having to run up and push E. I was not aware until I saw someone else shoot them.