  We investigate the interference pattern in the spectrum of non-dipole
bremsstrahlung on two amorphous foils. Apart from suppression at lowest
$\omega$, the spectrum exhibits an enhancement adjacent to it. In classical
electrodynamics, the net effect of suppression and enhancement proves to be
zero. We study the location and the origin of the spectral features, comparing
predictions of full Moli\`ere averaging with those of the Gaussian averaging
with Coulomb corrections to the rms multiple scattering angle. Comparison with
experimental data, and with previous theoretical predictions is presented.
