so about 2 months ago i got a brand new trek 7.1 FX and its been making this clunking noise pretty much ever since i bought it. i took it to the lbs where i bought it and he keeps adjusting the derailleurs because he thinks its that but i dont think it is. im very new to bikes and i have no idea how to fix anything so i need your help.
theres the video and sorry its kinda windy and it was filmed at night. also it is not the bottle cage or water bottle as the noise happened before i added that to it. this happens randomly both only when i go up hill and down hill while pedaling but never while coasting or when i pedal it with my hand while lifting the rear wheel up.
bike works perfect other than the noise but it is very very annoying to see a brand new 500 dollar bike do this. i know its impossible to diagnose the exact problem online but any suggestions are welcome.