In the past, when you were watching TV and a commercial message was broadcast at a higher volume than the preceding program, it could really startle you. To prevent this, the CRTC requires broadcasters to follow rules aimed at ensuring that television programming and commercials are broadcast at a similar volume.
Effective September 1, 2012, Canadian broadcasters and television service providers (e.g., cable, satellite, and IPTV providers) must follow international standards for measuring and controlling digital television signals, and must ensure that TV commercials are broadcast at a similar volume to programs. The standards apply to digital television services only. They are designed to ensure that you do not have to reach for the remote control when a show cuts to an advertisement. Broadcasters are also responsible for maintaining the volume of the programs themselves, to ensure that both programs and advertisements are transmitted at a relatively even volume.
Of course, the perception of loudness is based on many factors. It’s not just the volume, but the nature and content of the audio that play a role. What’s more, some sounds seem soothing, while others are irritating. So even a commercial broadcast at a similar volume to the program that precedes it can be perceived to be of different loudness. The following video demonstrates how loudness can be perceived differently. Video on loud TV commercials
If you think that a TV commercial is excessively louder than the preceding program, and that the perceived difference in volume is not due to other factors, contact your broadcaster or television service provider about your concerns. When considering making a complaint, remember that:
If you cannot resolve the issue by dealing directly with your broadcaster or television service provider, and you believe that they have not adopted the necessary measures to ensure that commercials are transmitted at a similar volume to the adjacent programming, you can complain to the CRTC (see Contact Us).
Your complaint must include:
 In 2009, a standard was set for measuring and controlling television signals in order to minimize fluctuations in loudness between programming and commercials.