Tweaker, the problem you have with levels is a widespread "loudness war" in pop music production, and they use expensive multiband compressors and limiters to achieve those high levels without distortion, so I wouldn't worry about music being louder on average than dynamic LFS sound. Thats just normal.
If LFS was to acheve those levels (and destroy dynamic variations btw) Scawen would need to hook some kind of limiter at the final stage of internal LFS sound mixer. Which is not impossible since he already put a simple echo in there. I'd like to see boost in LFS to be limited to something like 14 or even less. I'm quite appaled to hear many LFSers just crank that up and yet say that it sounds better. Don't they have any ears.
Sorry for the slight off-topic, working with sound is my job, so I notice more.
I just tested U22 breifly. I have Win XP SP1, SB Live with kX drivers, and it works well, even with Sound Blocks set to 1. There are very occasional pops and crackles and much more of them when echo is heard. Especially noticable in quieter road cars. Default Sound Blocks on 2 works better, of course, but still crackles close to walls. (if 1 block is 1/20th of a second then 2 blocks is old minimal setting of 0.10s, and 1 block would be 0.05s, right?) Btw, I never had any hearable sound lag in U20 and U22, in both I used 0.10s without problems.
Also, like someone else wrote, BF1 engine sound is notably kinda out of sync within itself: shifts and TC sounds different, sometimes sharper sometimes softer. Seems like little parts of sound get lost and skipped at the edges of those sound blocks. I think same thing happens in all the cars, like when revs go down in next gear after flat shifting in RAC for example, just that is less noticable because BF1 sound is most complex and things change very quickly in it.