  We give a large class of new supersymmetric Janus solutions in dyonic
$ISO(7)$ maximal gauged supergravity encompassing all known solutions appearing
recently. We consider $SO(3)$ invariant sector in which the gauged supergravity
admits four supersymmetric $AdS_4$ vacua with $N=1,1,2,3$ unbroken
supersymmetries and $G_2$, $SU(3)$, $SU(3)\times U(1)$ and $SO(4)$ symmetries,
respectively. We find Janus solutions preserving $N=1,2,3$ supersymmetries and
interpolating between $AdS_4$ vacua and the $N=8$ SYM phase. These solutions
can be interpreted as conformal interfaces between SYM and various conformal
phases of the dual field theory in three dimensions. The solutions can also be
embedded in massive type IIA theory by a consistent truncation on $S^6$. We
also find a number of singular Janus solutions interpolating between $N=8$ SYM
or $AdS_4$ vacua and singularities or between singular geometries. It turns out
that, apart from the SYM phase on D2-branes, all the singularities arising in
these solutions are unphysical in both four- and ten-dimensional frameworks.
