Connectivity Issue with McIntosh C2800 and MX121 – No Sound in Front Channels

Hello Audiogon community,

I recently purchased a McIntosh C2800 pre-amplifier to integrate into my home theater system and enhance my music listening experience. The preamp is currently connected via XLR cables to a McIntosh MC252 amplifier (which I plan to replace soon). My front speakers are Sonus Faber Olympica Nova III, paired with two SVS 4000 subwoofers.

The audio/video processor is a McIntosh MX121, and a separate McIntosh multi-channel amplifier handles the movie audio. I followed the connection instructions from the manuals. Two XLR cables run from the FL and FR outputs of the MX121 to the Balanced 3 input on the C2800 preamp. Additionally, a 3.5mm stereo cable goes from the Pass Thru on the C2800 to the MX121.

Despite checking the connections multiple times, I cannot get sound to pass through to the front channels when turning on the MX121

Any ideas or suggestions on what might be causing this issue?

Thanks in advance for your help!