This customer regularly drives from the South west to London and when he gets there the clutch drags badly. Previously he had noticed that the pedal was going down of its own accord so we fitted a new master cylinder. The pedal apparently is now ok but the drag problem persists. On local driving it's perfect.
If you google 'octavia clutch fault' loads of people have had similar issues but no cures. We did wonder if the hose might be ballooning when it's hot.
Some might say it's bound to be a DMF fault but I can't see quite how.

Anyone?