Poxy clutches!

So I've been researching and reading, but I've got more questions than answers now.

I've got an 07 2.0 TDi with 55k on. Roughly 10k/2 months ago I had the clutch and dual mass flywheel "changed" under warranty because of the vibration on tick over issues. Now under load the clutch has started slipping, and it's getting noticeably worse.

I've come to one of two conclusions, either they never changed the clutch, and the old damaged one is still in there, or they've cocked something up fitting the new one and the fault is developing as it beds in.

What do I do? I'm planning on taking it back to Audi but it's an intermittent thing, so I won't necessarily be able to replicate it to their engineer.

Any thoughts welcome...

Pete

ETA: Car is completely standard:icon_thumright:

Any ideas guys?

It's so intermittent at the moment I'm not sure it's worth being overly concerned about, or paying the inspection fee! I'll wait to see if it gets any worse, or to see if I can work out the conditions that provoke it so I can demonstrate it to a techie.

Maybe once every 1000 miles I'll feel a jolt, usually on the motorway or a long uphill drag, I noticed it once or twice before the "new" clutch/flywheel, but more regularly since it had the work.