Plasticky creaking/clicking sound at low speed from A-pillar area and across the top of the dashboard

[AbuG]

My lower B-pillar tapping sounds was getting reflected off the sunroof glass but when you get someone else to sit closer to it they can point out where it's coming from.

 

[Cocijo]

They dismissed my claims it was the sunroof knocking and told me it was the A-pillars (which I had also complained about rattling)
They told me that they'd already fully replaced a couple of sunroof cassettes on ZS's but couldn't find anything wrong with mine.

To be fair mine has only knocked one two occasions and as you said, it sounds like two panels knocking together.

Thanks for the update. I had a good look today and my knocking is definitely from the sunroof area behind the drivers seat. If I didn’t know better I would think that I’d left the tailgate half open on the latch. I can’t see anything obvious. It’s quite strange as it can be really loud and evident and then go away for a while. I intend to get the dealer to look at it, but like many things it would be better if it was either there and noisy all the time or not at all! I can guarantee it will be quiet when they try it!