Recently, a viewer called S Wheeler found a flash in the Las Vegas shooting footage that seems to come from suite 32 1 34. This short video gives a 3D reflection analysis of this flash.
Sources
"Is this a muzzle flash from Mandalay Bay?" (S Wheeler)
"Las Vegas Shooting. Muzzle Flash from Mandalay Bay Room 32 134"(nserve)
"Sundance Helicopter employees recount night of Las Vegas shooting" (Las Vegas Review-Journal)
"Tragedy in Sin City" (Daily Mail)
http://www.dailymail.co.uk/news/article-2071406/Las-Vegas-helicopter-crash-5-dead-Sundance-Helicopters-accident.html
"Official Radar Video From Night Of The Las Vegas Shooting" Truth Tracker