  The High Density Effective Theory formalism is used to calculate the low
energy properties of the phonons and gluons in the
Larkin-Ovchinnikov-Fulde-Ferrell (LOFF) phase of two-flavor QCD. The effective
phonon Lagrangian for the cubic crystal structure, which is favored according
to a recent study, depends, at the second order in the derivatives, on three
parameters which we calculate in this paper. We also compute for soft momenta
the effective lagrangian for the gluons of the unbroken SU(2)_c group, both for
a single plane wave structure and for the cube. In both cases the Meissner
gluon mass vanishes as in the case of complete isotropy; on the other hand
there is a partial Debye screening due to the existence of blocking regions on
the Fermi spheres. For the single plane wave structure the gluon dielectric
tensor is non isotropic, while it is isotropic for the cubic crystal, in spite
of the intrinsic anisotropy of the structure.
