I'm sorry to hear that your router is making noise and appreciate you have followed tips on the forum without success.
Our Products Team have had discussions with the router manufacturer about this, and have been advised that the reported noise levels are within accepted tolerances and not an indication of any problems with performance or any defect. As such, we would not replace the router on this basis as any replacement will likely be the same.
You may find that the noise levels are most obvious at the 5GHz frequency in which case you can try it on the default 2.4 GHz.
Thanks - LF
If this post resolved your issue please click the 'This fixed my problem' button