I am a year late… but I use this exact unit on my JL subs and it eliminated (at least greatly reduced) the electrical buzz in my system. I use the JL crossovers in the subs and they pick up electrical noise, probably because JL is junk.
this electrical buss does not go up and down with volume and goes away if I don’t use the subs. Sometime I will buy new subs from a different brand.