Maybe double-check your connections, as RCA's are paired vertically and XLR's are paired horizontally?
Bel Canto Pre2 Preamp plays in mono.
I'm auditioning a used Bel Canto Pre2 preamp and all inputs play in mono. I'm using the input 1 balanced for my DAC and input 2 RCA for my phono stage. Both play only in mono and I can't find a configuration setting for that. Anyone have any ideas? I've checked all my cable connections of course paying special attention to the connection from the preamp to the power amp.