Get the Rotel RMB-1585 class AB five-channel amp. It’s way better than your Rotel RMB-1565 class D amp. Rotel class D amps are total failures. If you want to get Rotel you will have to go with their class AB amps such as the RMB-1585. Night and day better than the RMB-1565 class D amp. Rotel is very well known for their class AB amplifiers, that’s where the Rotel is good at.
I think you purchased the wrong Rotel amplifier (RMB-1565 class D amp).
The RMB-1585 is a beast built like a tank weighs in for about 80 lbs. Equipped with 2 large main toroidal transformer power supplies for all 5 channels. It has unlimited reserve of power very powerful and hugely dynamic with lots of dynamic headroom. Very refined and musical sounding amp especially for the money currently retails for $3k new. Has smooth highs and tonally it’s on the warm side. Very refined, smooth sounding amp. The sound is fulsome with midrange bloom that’s to die for.
For $3k new retail price IMO it’s a bargain. Unlike the Rotel class D amps, this RMB-1585 class AB amp sounded fullsome throughout the audioband with full mid-bass, bass and mid-range. It has a buttom end grunt one expects from much higher priced amps. And the bass is well defined and very controlled.
The RMB-1585 sounding very fluid and liquid whereas the Rotel class D amps sounded somewhat dry and kinda sterile lean thinner sounding.
Highly recommended!