Right side is about 1dB louder than the left side - is this normal?

Hi guys,

I noticed that the right output of my Pro-2 is about 0,9-1dB louder than the left one. Is this normal and can be fixed by simply adjusting the incoming gain on the interface, or is there something wrong with my unit? My OB-6 which has zero digital in its signal flow has a difference of 0,2-0,3dB left and right.

Would be great if someone could help me out!

Thanks and all the best,
Greg