Ayre K-5xe preamp and turntable issues

I have 2 turntables with built-in phono pre-amps.  I have connected each through my Ayre K-5xe pre-amp.  In both cases the volume is so low, even if I turn the Ayre all the way up, the sound is minimal.  I am connecting the RCA cables from the turntable to the RCA ins on the Ayre.  Might anyone help me understand what the issue might be?  Much thanks.