I'm currently running pretty advanced and stocked settlements at 3 specific locations (Spectacle Island, Sanctuary Hills, and the Drive In). They've all hovered right around 75% happiness for the past 6 days (real life time) and crash to about 50% each every day. They'll be perfectly fine when I go to the specific settlement that is struggling, but as soon as I fast travel to another location, another settlement plummets. They're all around 18 settlers, 60 food and 60 water, 60 power, 140 defense, and 30 beds. For example, every time I leave Sanctuary to go to Spectacle Island, the 34 beds that I have on the settlement mysteriously vanish on the Pip-Boy Workshop screen and has "0" in it's place. But when I go back they suddenly appear on that menu, and when I talk to the settlers with all 34 beds listed, they say there's a bed shortage. Does anyone have any suggestions to fix this problem, or can I even fix it in the first place?

I've heard that deleting all TVs and jukeboxes will prevent this. In my experience, simply turning them off works too.

I gave up on the settlements. Now I just collect the purified waters before I go on a mission or exploring. Even with 100 defense, the settlement gets destroyed and settlers die if I don't help. Even with an enclosed permiter wall with 2 levels of concrete shack floors, metal walls and metal roofs the enemies still get inside somehow and destroy my water purifiers and crops. It doesn't make sense. But at least the settlements fix themselves.

heh I stop caring about settlement happiness levels. as long as it's 50% or higher it's really doesnt matter.

Yeah its a bug. And removing tvs (or at least removing power to them) seems to fix it