Yes, constantly. I've been recording sessions in my spare room for about three years now and the static burst thing is almost like a signal at this point - I know to pay attention because something's coming through. Had one last October that was genuinely startling, loud crackle followed by what sounded like a woman saying "still here." Clear as anything.
What I find interesting is the burst doesn't always come right before. Sometimes its a few seconds, sometimes longer, like whatever is trying to communicate is building up to it. My old Olympus recorder does it more than the newer one I bought last year which I find odd.
Anyone noticed whether certain locations produce more of this than others? I've only ever done it indoors but a mate of mine swears he gets it more in older buildings. Would love to hear if others are tracking the gap between the static and the actual response, because I reckon theres a pattern there if we look properly.