How do I fix my severe listening deficiency?
I understand grammar used in sentences I read, have a pretty good stash of vocab (a couple thousand, maybe even three plus grasped words, and a thousand plus not really firmly rooted in my head yet), so my reading is pretty good. However I don't speak or communicate in the language, and neglected my listening, which is starting to change now that I realize how lacking I am there.
So when I listen, I just feel a bombardment of syllables that I can't make out in time, which makes me lose focus on the new info coming in. As a measuring stick, I can understand 40%~ of stuff in TTMIK iyagis 1-8, and can recognize the beginnings of some sentences in dramas with English subtitles, too long and I zone out of focus.
So my question is, is it because I don't communicate in the language that's causing me to not be able to understand and anticipate the flow of conversation? Does speaking help listening, or the other way round? Is the solution to this truly only through listening and listening?