I found in other forum that you can use F45 and/or F39 to boost the bass in cars with HK Audio.

Has anyone done this? What is an optimal setting?

 

Did you ever get an answer to this? I’m curious about the same thing.

 

I've been looking at BimmerTech as well. Are you saying there night be a simple code upgrade? Sweet (maybe).
2019 CM S All 4 w/HK and CarPlay is ok, but certainly not high fidelity
I've looked at BimmerTech's AlphaOne "drop-in" speakers and amp. Looks super cool. Watch lottsa U2B vids about installs. I'm saving up for that one. Probably start with the amp. then move on to the speakers-full set/replacement.
https://www.bimmer-tech.net/
https://www.bimmer-tech.net/speakers...lifier-for-bmw