Two-level systems (TLS) interacting with conduction electrons are possibly
described by the two-channel Kondo Hamiltonian. In this case the channel
degeneracy is due to the real spin of the electrons. The possibility of
breaking that degeneracy has interest on his own. In fact, we show that the
interaction of the conduction electrons with a spin-orbit scatterer nearby the
TLS leads to the breaking of the channel degeneracy only in the case of
electron-hole symmetry breaking. The generated channel symmetry breaking
TLS-electron couplings are, however, too weak to result in any observable
effects. Our analysis is also relevant for heavy fermion systems.Comment: 6 pages, LaTeX using epl style, 3 eps figure