The power spectrum of ~630 days of full-disk solar velocity data, provided by the GOLF spectrophotometer aboard SOHO, has revealed the presence of mode-like structure well beyond the acoustic cut-off frequency for the solar atmosphere (nuac ~5.4 mHz). This kind of structure has already been observed in intermediate and high spatial resolution oscillation data (Duvall et al. 1991), but never before in integrated data like BiSON or IRIS. This is probably due to the higher level of noise that are inherent to the earth-based experiments. In this contribution, we analyse the observed peak structure (nuac < ν < 7.5 mHz) and we describe the theoretical analysis of such signal.