It is a phenomenon that has annoyed television audiences for years - the advert break begins and suddenly the volume is cranked up.
Despite numerous complaints, broadcasters have previously tried to suggest that the jump in noise is a figment of viewers' imaginations.
But now the Advertising Standards Authority has proven it exists and is taking action against ITV.
The regulator today ruled that eight commercials shown during a recent broadcast of the Adventures of Sherlock Holmes on ITV3 were too loud and broke the Advertising Standards Code.
HA! I knew it!! I knew it wasn't just my imagination!
Is it a world-wide phenomenon, or just in the UK?