Online videos featuring strange sounds emanating from the heavens are attracting a lot of attention, but an audio engineer says they're easy to fake.

Richard Dolmat of the Digital Sound Magic Recording Studios in Vancouver applied his professional ear to several popular "strange sounds" videos that were recently broadcast on CTV's Canada AM.

For his analysis, Dolmat says he started by looking for obvious signs the soundtracks didn't match the videos. The sound of birds chirping in the nighttime video of The Pas, Man., for example, raised his suspicion.

"I know that in Canadian winters, you don't get that many bird active in the snow in the middle of the night," he said.

But that wasn't the most striking clue.

Comparing The Pas video to one depicting strange sounds over Conklin, Alta., Dolmat said they both feature "the exact same birds with the exact same rhythm pattern timing."

Lining the videos up for a back-to-back digital comparison, he found that "they are exactly the same sound."

Comparing his professionally-tuned ear to the palate of a chef who can tell you what goes into a dish just by tasting it, Dolmat said he was able to determine the components of the ominous soundtrack.

"I broke the original YouTube video sounds down to an alligator roar, two lion roars, some white noise, a stone dragging on concrete and three waterphones," he said in an interview from Vancouver on Wednesday.

"They've all been pitched down with a ton of reverb and compressed and that's what you get," explaining that's an audio engineer's favourite method of coming up with scary sounds. "Fade in, fade out and you're done."

Dolmat's explanation could indeed account for the host of videos that have sprouted up online, the most popular of which is a 12-minute video featuring strange sounds supposedly heard in Kyiv, Ukraine.

That video has had more than 2 million hits since it was posted on YouTube in August, 2011.

The strange sounds video from Conklin, Alta. has also racked up nearly 2 million views since it went online in mid-January of this year.

Even if these videos are what Dolmat believes are a "textbook viral marketing ploy," his debunking does nothing to explain the mystery sound phenomenon for those who have heard them first hand.

In recent days, residents of Windsor, Ont. have been complaining about the resurgence of an annoying, and in some cases sickening, airborne noise.

A seismic investigation has narrowed the source of the so-called 'Windsor Hum' to a one-square kilometre area of the heavily industrialized Zug Island across the U.S. border in Rouge River, Michigan.

Another recent spate of strange sounds reported from North Battleford to Saskatoon, Sask. was explained by a University of Saskatchewan professor as a naturally-occurring "electromagnetic noise."