RS150 analog input lag

Hi!
I have a dual purpose system for music and movies. Yesterday i sold my preamplifier and connected the RS150 directly to my power amplifier using XLR cables. The problematic part is that i thought i was clever and connected the signal for the front speakers from the AV receiver to the analog inputs of the RS150 the same way i had done with the preamp but the front speakers play too late and create a nasty echo that way. Is there a way to get rid of this lag?
I tried adjusting speaker distance in the AVR setup menu but it doesn’t allow distances as great as needed to make the echo go away.

Another option would be to connect the AV receiver straight to the power amp but then i’d have to reach behind the hifi rack and turn the knob to RCA stereo (there are also XLR mono and RCA mono positions on that knob and i’d have to turn it without seeing which position is selected) and back to XLR stereo every time i’m switching between music and movies.

Any ideas?

I just finished separating my Stereo from Hometheater.
I bought a Stereo PRE Amp, which has a HT passthrough.
Before, I had my Rose connected with XLR out to my Balanced IN on the AV processor.
Now with the new PRE, Music is dramatically better. My MONO are attached to the PRE, and I’m good with it. And I can do everything by Remote.