Tech support at Korg got back to me and said my Panasonic
SV-3700 will work with 44.1K from the 168RC.  It's well known
that the 168RC operates under its own clock at 48K, but when
slaved to another device at 44.1K, most dat recorders' spdif
(Tascam, Sony) are confused by the 168RC's 48K flagging of a
44.1K datastream. It's not a question of whether the dat recorder
is "professional" or whether it can be set to accept 44.1K spfif.