2017 Mazda CX-9 front suspension clunking/knocking noise

Just inside each strut tower (the towers each have 3 silver bolts/nuts) there is a brace/bracket between the two towers (black horizontal bar in picture below). Each end of this bracket has 2 black bolts/screws that hold it in place and these are what need to be tightened. 12mm IIRC.

I have a similar clunking noise from my front shocks.
Could you please re-attach the pics. They are not available here.
 
My cx 9 has about only 6000 miles. Pretty much every time when I go over the speed bump, the front driver side suspension will make clunking or knocking noise. First time took it to the dealer, they replaced lower control arm but the noise is still there. The second time they said that it was the windshield cowl(loose or broken pin). I am about to call the dealer for the third time. Does anyone else having the same issue? What could it be?


In the above link, its the video that I took which show the clunking noise. I dont know how well you guys can hear it. But, its the same recording that I showed it to the service writer.
I just had this same issue on my 2019 CX5 with 11k on it. This was a subframe bolt that was not torqued properly from the factory, and was loose causing the clunking sound upon stopping, this was after I was told it was a lower control arm, a 30 year master tech found this issue. Extremely unsettling to have a frame issue on such a new vehicle. He said he has seen this issue on every model and year since 2010 except Miata. Have yours looked at! Front left bolt on subframe.
 
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2019 CX-9 GT
Had the same issue on my 2019 CX-9 GT. I tightened the strut tower bolts (strut brace bolts were really loose) and that cured it. Only 8700 miles at the time.
 
I have a similar clunking noise from my front shocks.
Could you please re-attach the pics. They are not available here.
Just took mine to the dealership today. had the same issue and all FIXED! under warranty. Thanks for the tips to explain and find a spot near the dealership with bumps. The bolts were tightened in the Strut assembly