AD8363 With Floating TCM1 & TCM2 ?

Hello All,

Using the AD8363 but am getting a logarithmic slope close to 40mV/dB instead of the specificed 52mV/dB.  Could this be caused by leaving the TCM1 and TCM2 inputs floating. Is  recommended to have these pins connected to some potential (table 4 page 18)?  I don't need temperature compensation so I assumed that I could leave these pins floating.  Are there recommended resitor values for a resistor divider to vref?