I do experience the client close as well, I`m trying but did not find any pattern about the closeing, Since last update the game close decreased, but still have pretty high rate when it happens.
I`ve found if i do less memory usage on my pc next cabal it maked slightly less chance for closeing.
Like bacgrond you tube musics quality derease helped a lot. I got at least 16G memory so not rly on my pc.
As i see it mostly close when the game is loading, like warp, change chanel or startup the game.
I suppose you guys allready know this, so i do not think I help any, but i hope i do.