Something like this m8, this is something im getting atm sound a bit like your issue, with mine the whole area above the line turns white when the player fires a collected gun
and this one without scrolling clouds showing the lines of the skybox doesnt matter what the camera distance
ewe spotted a spelling mistake in the helm doing that one lol
EDIT: managed to cure this by swapping the ssunset skybox to the red skybox so it seems the scrolling clouds might be the issue p.s rolfy's day and night skybox has also stopped working :/
Intel i5 4950 Quad core 3.3ghz AMD FX 6300 x6 cores 3.5ghz(unclocked)
8gb Ram 8gb Ram
AMD Radeon 7570 1gb AMD Radeon HD 6670 2gb
and a well fed mouse on a wheel
I only smile because i have absolutely no idea whats going on