When I last performed maintenance to the window sliders, I noticed the doors had not been soundproofed yet. Bought me a big mat on Aliexpress and went to work today.
Door card removal is very easy on the Volvo, so I was done in a very small time frame, which is always nice. The impact of such a simple thing like soundproofing is always noticeable, as the resonance from the tinny doors are removed, which allows for better sounding music + less cabin sound/drone.
Highly recommended & easy to do yourself!