strange smell after faucet runs for a while

[andrewc2005]

Ok I can't figure this out. Whenever I run the faucet in my kitchen for a few minutes suddenly a really bad smell hits the air. It's strongest under the sink. I thought it was the trap but the smell still comes back after I had it replaced. The plumber didn't believe me when I told him about the smell, he said it was impossible.

Anyone have any ideas?

[bamboo]

A leak in the vent pipe will do this

[Gary Niskanen]