SDMT and Jet Engine Sound

[HatboxHaint]

I noticed something two weeks ago that I didn't remember from 2014. Everytime we rode SDMT when you come out of the loading bldg and go down and around the first curve there is what appears to be a speaker on your left side playing what sounds like a rocket or jet engine blasting off....not sure how that fits into the #story. We rode SDMT 3 or 4 times and heard it blasting every time. Anyone else notice this and/or have an explanation/thought?

 

[ThornXBL]

I don't know if it's a speaker or the sound of machinery/hydraulics, but my GoPro picked up that sound on the left side after one of the curves a little before entering the mine... I thought it was odd hearing it on playback; i didn't recall noticing it while riding.