Cascadia fridge knocking noise..

Anyone have an idea on how to get these fridges that come in the cascadias to stop knocking...I have tightened up all the plastic bottles in it,used foam to snug up how the shelf inside fits in the slider track..I keep everything fairly snug inside but I keep hearing this knock like sound..
Seems to me its the guts of the fridge workings making this noise..Anyone ever take it apart and stuff the back area some to keep compressor ect from maken this noise....Both my cascadias made same noise and it always started about 2-5000 miles after it comes from dealer..I swar im gonna loose my effing mind over this..
I have cleaned out my bunk,moved stuff around just to see if its the fridge for sure and it seems to be something in or around the dang fridge...Suggestions please n thanks..