hissing noise vacuum leak?

Just had a new EGR valve put on...$375. The dealer told me this would fix a hissing problem/vacuum leak noise. The dealer was wrong. This noise has been going on for 6 months+. No engine light...car runs fine. 06 Jetta TDI with 106,000 miles.

The guy that changed the timing belt and installed the new EGR tracked the noise ...he believes...back to the turbo. We had troubles with the waste gate early on, but no trouble after we stopped using homebrew.
We stopped using homebrew soon after we figured out it was causing the wastegate issues....probably before 25,000 miles.
The mechanic that did this work advised me to take it to a turbo shop.
Any ideas???

I presume you hear it during acceleration?

If you do, take the EGR to upper intercooler hose off, and check the nubs. If they are flattened or ground down, the hose can be fixed fairly easily.

There are a couple more connections, including one on the turbo outlet. Make sure they are all secure.