hi all,im finding my screenwash gets very smelly after a few weeks in my 2016 a6,i flushed out the system with milton a few months ago but its bad again now.maybe im topping it up too much and i probably should let it run out each time?has anyone else come across this?greg

Common problem Gregg, particularly in the summer months. Winter months? Far less common. 
I seldom fill mine more than half full in the summer, since you will find it can actually coagulate as well, and block the jets. 
Make you are using, and ready-to-use or concentrated? 

Kind regards,

Gareth. 

thanks gareth,im using concentrated but ill definitely take your tip and half fill it from now on.

Sounds good Gregg. Just goes to smell - and act a stagnant water. I think increasing the concentration and just adding small quantities at regular intervals is the best route to minimising the issue. 
Kind regards,

Gareth. 
p.s. I’m averse to the Ready to Use variant, on the basis that I don’t like paying a premium for water, and of course it just adds to the bank of recycling 5 ltr containers.