A set of three Butson type matrices found by R. Nicoară, A. LaClair, N. Geist and A. Wintenberg in May 2016 (UT, Knoxville).
Defect is $d(M_{13B})=1$.
Extension of $M_{13B}$ to a $1$-parametric (maximal) affine family:
$$R_{M_{13B}^{(1)}}(a)=\left[\begin{array}{rrrrrrrrrrrrr} \bullet & \bullet & \bullet & \bullet & \bullet & \bullet & \bullet & \bullet & \bullet & \bullet & \bullet & \bullet & \bullet\\ \bullet & \bullet & \bullet & a & \bullet & a & \bullet & \bullet & \bullet & a & \bullet & a & \bullet\\ \bullet & \bullet & \bullet & \bullet & \bullet & \bullet & \bullet & \bullet & \bullet & \bullet & \bullet & \bullet & \bullet\\ \bullet & \bullet & \bullet & a & \bullet & a & \bullet & \bullet & \bullet & a & \bullet & a & \bullet\\ \bullet & -a & -a & \bullet & -a & \bullet & \bullet & -a & \bullet & \bullet & -a & \bullet & -a \\ \bullet & \bullet & \bullet & a & \bullet & a & \bullet & \bullet & \bullet & a & \bullet & a & \bullet\\ \bullet & -a & -a & \bullet & -a & \bullet & \bullet & -a & \bullet & \bullet & -a & \bullet & -a \\ \bullet & \bullet & \bullet & a & \bullet & a & \bullet & \bullet & \bullet & a & \bullet & a & \bullet\\ \bullet & -a & -a & \bullet & -a & \bullet & \bullet & -a & \bullet & \bullet & -a & \bullet & -a \\ \bullet & -a & -a & \bullet & -a & \bullet & \bullet & -a & \bullet & \bullet & -a & \bullet & -a \\ \bullet & \bullet & \bullet & a & \bullet & a & \bullet & \bullet & \bullet & a & \bullet & a & \bullet\\ \bullet & \bullet & \bullet & \bullet & \bullet & \bullet & \bullet & \bullet & \bullet & \bullet & \bullet & \bullet & \bullet\\ \bullet & \bullet & \bullet & a & \bullet & a & \bullet & \bullet & \bullet & a & \bullet & a & \bullet\\ \end{array}\right]$$so that, for $a\in[0,1)$ one has
$$M_{13B}\mapsto M_{13B}^{(1)}(a) = M_{13B} \circ {\rm EXP}\left(2 \pi i R_{M_{13B}^{(1)}}(a)\right).$$