The corrugated pipe runs a very convoluted route to the reservoir bottle, best seen when the wing is removed. There could be a kink, mine is fairly slow to do (like everything else under the bonnet).

and is probably the one thing I check before every drive so that filling up is minimal as the washer fluid seems to evaporate a little due to the engine heat. There is also the little blue pipe inside the larger pipe that avoids airlocks - that could also be the problem if kinked or blocked.
Regarding your g/box shunt/chatter noise, after a couple of thousand more miles, get the dual mass flywheel checked. Mine had to be replaced by the factory at 12k miles - all seems ok now, chatter is now a whisper.