I have all issues stated above. I am SR with the Mac system. I already have had one speaker replaced due to rattling (passenger front door), the speaker replacement did nothing. I have interior door rattles due to stuff continuously becoming more loose or tape falling off. I have door pillar issues still and plenty of noises as a result being driven and audio playing. After seeing inside the door while dealer was changing the speaker, it is obvious that these problems will never go away. The door interior is not sound proofed well. Lots are things able to flop around in there, let alone lack of sealant at bolted parts to stop vibration. The Mac system isn't much better than the alpine in the 2019 GC, but has deeper bass. I suspect this has done the bulk of the damage.
I have annoying headliner buzzing noises while driving without audio. I have pressed hard on the a pillar to headliner intersect area and it has stopped. I suspect a clip or sticky tape wasn't holding well. I have to do this periodically. I also found a rear side panel vibration due to a loose panel, but was sounding like it was coming from the front, it was reflecting off the front glass. I drove around and made my wife hop around to different seats for a bit to find it.
Your seat memory issues might be the b pillar noise. There are parts inside the pillar contacting causing a metallic clicking/clunking noise. Not sure if it is the same as you hear. There is another thread about that already. I also had a protective cover underneath my jeep that was not bolted and was flapping in the wind while driving. My pics are in the b pillar thread.
If my dealer can fix all of the other issues in less than 14 days, If I still own it in a month due to my lemon law suit, it will go to a pro audio shop to be lined with sound deadening mat everywhere. The road noise is horrible. My 2012 GC was ok, the 2019 GC was better. This 21 GCL is worse than both, AND is supposed to have active noise cancelation thru the speakers to cancel the noise, go figure.