I have to agree with this. I also have times where it seems like the soundscape just straight up breaks due to too many overlapping sounds.

Most of the time I just play with the music off as well and just play a song of my choice in the background.

Weapon sounds also need to be overhauled, the corvette autocannons are a great example of this since they just use what sounds like a stock sound GAU-8 firing loop.

I too am having this issue. I've been playing for a long while before this, but can't find anything on how to link my steam and Grey Box accounts.
On steam though a DEV did post this giant list of codes for the stress test before the main launch, so I would think that if you can find a un-used code you may be able to link your account through the downloaded game.