The sounds you're hearing during NBC's Olympics coverage may not be what you think.

Sound experts say the network's chase boats in the River Thames were so loud that they drowned out the natural sound of rowers in competition. The chase boats are needed to get great shots of the rowers, but they say the network believed something was lost so they replaced their actual live audio with a pre-recorded sound track of rowing. So, that's what viewers are actually hearing.

NBC secured some 600 sound technicians to enhance the audio at sports venues that also include diving and archery. IU Communications Professor Emeritus Herbert Terry says he doesn't think there's a big problem here. However, Terry adds that he thinks it's important for networks to admit what they're doing for the transparency sake.