Yep, the scuttle panel sealing and I also bet the drain holes in the upper front wing are blocked so you've got a puddle of water sloshing around next to the ECU. VAG group cars have some great design faults!
Recommend you take the wiper arms off, remove the scuttle completely and then clear out all the detritus from either side and make sure the drain holes run free. I now do this every couple of years on S3 and Cordy as part of routine maintenance.