Help! 2021 CX-5 undiagnosed engine knock

[RZRider]

Idler Pulley Bearing, Torque Converter Bolts?

 

[Motozona]

Hi everyone, I hope you can help me out - this is driving me nuts.

I have a 2021 CX5 GS, skyactiv engine. Purchased new, all regular oil changes by dealer.

There's this engine chugging/knocking sound that varies with RPM, sounds almost like a diesel engine when it's there. No engine lights have ever come on.

But it's very intermittent. Will be present in summer or winter. More noticeable in the cold, or just after starting, but it'll last through my 20min commute. Happens in the summer in 20*C too.

I've brought it to the dealership twice but each time it isn't there when they examine it and tell me they don't see anything wrong.

I'm reaching the end of my warranty period and really worked this will cause premature engine failure and brick my car :/

Video attached and I'll add some other videos of abnormal/normal sounds in the comments.

Anyone have ideas or advice?
Thank you so so much in advance!
View attachment 333712

My 2021 only has 16 k on her and doing this. Lifters can go dry after sitting but they should fill within seconds , not minutes. Mazda engineering must know this . It sounds to me that the money people are ignoring the real makers of this company. To Mazdas demise if I'm correct.