Wipers clunking

[sbridgey]

this evening whilst driving home along the motorway my wipers developed a clunk at the top of the sweep, it reminded me of the noise they make when the seating peg isn't in properly by the wiper arm mechanism below the scuttle panel. the thing is the clunk sounded like it was coming from the top left of the window.

any ideas what it is?

 

[barker22]

I had a bit of a clunk for ages, drove me insane, I had the plastic spoilers on my wipers and it was that spoiler hitting the glass as the wiper changed direction, pulled it off and it went away

 

[sbridgey]

I have aero wipers so i don't think that is the issue, anyway it wasn't doing it today, must have been something to do with the snow around the wiper mechanism