Question about Brennenstuhl Premium-Protect-Line

I use the power strip for my computer + amplifier. A large part of the background noise could be suppressed in this way (but unfortunately not all of it).

There is still a slight noise, but it is not audible during operation. Only when the speakers are on and nothing is running can the noise be heard very softly.
(I think this could also depend on the speakers, so no guarantee that it will work).

Unfortunately, I cannot offer any help with your problem. I use the multiple connector strip in the basement.