@M0N so, what can I say?
This little 19€ gadget has actually fixed my problem … It has ACTUALLY worked!!!
The RNHP is absolutely DEAD silent. The whistle is COMPLETELY gone with it and I’m lost for words honestly. This little thing actually does its job as avertised and I’m completely shocked.
I’ve tested the RNHP without it too to be sure it was still the same, which it was, so it’s actually doing its job! Completely lost for words.
I can recommend this little purifier MORE THAN ANYTHING and I’m so incredibly happy right now that I found a solution that lets me keep the RNHP and be happy with it. Unbelievable, really.