Help

It’s interesting in that both companies are or were under the same ownership. 

One would think those products may be synergistic.

I would by a few Akiko Audio Tuning Sticks (XLR/RCA) and try plugging them into various components.

I had one too. I listened to a lot of music. But there were no such problems. Recently I found a website https://www.styngr.com/ There's a huge library of songs for video games. Now I listen to music through another audio system. 

Go to a dealer and try to find something that sounds good to you.  Tell them the issues you are having with your system and they may be able to assist you. 

@fdfrank 

Many years ago, I had a Rotel amp + Rotel CDP + B&W speakers. 

This was a very fatiguing system for my tastes-- I didn't hang onto it for long.   

Can you perhaps borrow a different transport/cdp and amp from a friend and try each in your system?  Without being able to isolate which component is producing the sibilance, it'll be difficult to remedy.