  The multi-Higgs models having spontaneous CP violation (SPCV) and natural
flavor conservation (NFC) lead to a real CKM matrix $V$ contradicting current
evidence in favour of a complex $V$. This contradiction can be removed by using
a generalized $\mu$-$\tau$ (called 23) symmetry in place of the discrete
symmetry conventionally used to obtain NFC. If 23 symmetry is exact then the
Higgs induced flavour changing neutral currents (FCNC) vanish as in case of
NFC. 23 breaking introduces SPCV, a phase in $V$ and suppressed FCNC among
quarks. The FCNC couplings $F_{ij}^{d,u}$ between $i$ and $j$ generations show
a hierarchy $|F_{12}^{d,u}|<|F_{13}^{d,u}|<|F_{23}^{d,u}|$ with the result that
the FCNC can have observable consequences in $B$ mixing without conflicting
with the $K^0-\bar{K}^0$ mixing. Detailed fits to the quark masses and the CKM
matrix are used to obtain the (complex) couplings $F_{ij}^d$ and $F_{ij}^u$.
Combined constraints from flavour and CP violations in the $K,B_d,B_s,D$ mesons
are analyzed within the model. They allow ($i$) relatively light Higgs, 100-150
GeV ($ii$) measurable extra contributions to the magnitudes and phases of the
$B^0_{d,s}-\bar{B}^0_{d,s}$ mixing amplitudes and ($iii$) the $D^0-\bar{D}^0$
mixing at the current sensitivity level.
