You can also put expressions in the display text. For example, to only show bit depth and sample rate when bit depth is greater than 16,
if(compare([Bit Depth],>,16),[Bit Depth]//formatnumber([Sample Rate],0), )
will only display the bit depth and sample rate if the bit depth is great than 16. If >16, this will produce 24/96 for example. The formatnumber expression will remove the .0 for 96.0. You need the // since one / is a special character in J River.