exhaust resonance? ATMM?

[JTMachineDesign]

2019 5.7l BigHorn 6400 miles as I'm decelerating foot-off throttle I often hear what sounds like a resonance in the exhaust system start quietly and increase in volume until the tranny downshifts, and it starts all over again until the next downshift... any braking or throttle application stops it.

could this be the ATMM problem I've been reading about? there's some buzzy-vibration too but it doenst sound mechanical to me... what do you guys think?

 

[Big CountryRR]

I have a 2020 Laramie and just did a muffler delete. 1st off it sounds amazing, 2nd I dont notice any of the sounds your describing. 3rd these trucks are awesome. 1st RAM here.....I know a complete newb.

 

[raven_DT]

Is it MDS resonance that many owners experience?