The easy thing to do is experiment with speaker placement and treat the first reflection of the speakers with something that absorbs the treble. GIK Acoustics is what I use and it's very reasonably priced. I think I paid about $200 shipped for my panels IIRC
I've never liked the treble in the many Rotel components I've heard but I haven't heard your particular one.
I've never liked the treble in the many Rotel components I've heard but I haven't heard your particular one.