In the probably first successful photon correlation spectroscopy experiment on a crystalline solid, inelastic light scattering of vibrating random-field-pinned domain walls has been observed at subkilohertz frequencies in the uniaxial relaxor ferroelectric Sr(0.61--x)CexBa(0.39)Nb(2)O(6). In the paraelectric relaxor phase the response of polar nanoclusters becomes overdamped and Rayleigh-like.