Completely depends on the project. For general, everyday work, I’ll go out for a day or two once every two or three weeks. For something that needs more detail or collaboration, I’ll go out for a week and then not go back for a month or five weeks. If I’m working on a project outside of my normal office (I mentioned Guam and Amsterdam, but I’ve had projects elsewhere, too), I’ll work from home while I can and then travel there for two to three weeks and during that time I wouldn’t travel to my actual office for months.
What about when wearing (really good) noise cancelling head phones? Everything you’ve mentioned is when there is some sort of noise going on, but it’s it also happening with everything cancelled out? A few people have pointed out Auditory Pareidoilia which is your brain trying to find words/pattern/meaning in the noise it is hearing, but is it also doing that when the only sound it can hear is it’s own blood whooshing though your veins, which it should be used to? What about in a sensory deprivation tank?
There’s Hearing - which is what the all the tiny bits of your ears connected to the nerves do, then there’s Perception - which is how your brain interprets the information it receives from the nerves connected to your ears and puts it back together. Basically, your brain is working overtime to try to figure out why you are listening to the noise you are listening to. As long as it’s only happening in those situations described and, as others have said, it’s not voices telling to do anything.