That is what that B string feels like - what a bad boy string - it needs plenty of room to flub up and down, so the saddle height had to be raised. It barely fit all the way through the hole in the bridge to get it on the bass, but it eventually got pushed through! Noted on the muting, yeah, strumming it seems to trigger every other string.
Haha! The 4 string BEAD bass project spreads! It is a fun one. The serial # on the bass starts with IW17 , so, maybe the 17 makes it a 2017? I don’t think I bothered to find out from the seller when I got it, I was so new!