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tokens: PDSs obtained during the 20042005 outburst decay ( Qu et al. 2005 ). They found a QPO at 0.22 Hz in addition to a narrow peak (i.e. pulsation from the pulsar) close to that frequency (0.23 Hz). The QPO was detected when the luminosity was at a mid-flux level of the outburst, or even lower. The rms strength of this QPO also amounts to a few per cent in that work. The 0.22 Hz QPO was observed around the spin frequency in both the INTEGRAL ( Mowlavi et al. 2006 ) and RXTE data during the 2005 outburst decline ( Qu et al. 2005 ; Reig et al. 2006 ). In addition, Takeshima et al. (1994) discovered another QPO with a centroid frequency of 0.05 Hz and a relative rms amplitude of 5% in the 2.337.2 keV data from the 1989 outburst of V 0332+53. We do not find any signal of the QPO at 0.05 Hz, although we find the presence of a broad component at around that frequency (which may eventually turn into peak noise, i.e. QPO). The QPO detected in V 0332+53 at 0.22 Hz constitutes the first detection of a QPO riding on the spin frequency of a NS and points to a strong coupling between the periodic (i.e. the pulses) and the red-noise (i.e. broad-band QPO signal) components ( Qu et al. 2005 ). The existence of a QPO signal with a similar frequency to the spin of the NS suggests that they are related in some way. One model to explain this coincidence was given by Lazzati Stella (1997) and Burderi et al. (1997) . They proposed that the QPO originates in the magnetosphere around the NS. Additionally, they argued that the accretion flow is inhomogeneous near the surface of the NS, and that random shots are characterized by an arbitrary degree of modulation. The combination of rotation and radiative transfer effects should therefore produce a periodic modulation of the shots similar to that of any continuum X-ray emission from the polar caps. They proposed that a coupling between the periodic and red-noise variability should be frequently present in X-ray pulsars. In our case and in contrast to previous observations during giant flares ( Reig et al. 2006 ; Reig 2008 ) the QPO signal appears during the lowest of the measured fluxes ( ). If the QPO has an origin on the magnetosphere of the NS (and is not an artefact from our observations), it should be more visible when the accretion column is more tenuous (or even absent). In summary, it looks as if we might be witnessing the innermost parts closest to the magnetosphere surroundings during our latest observations, i.e. Obs. 611. 5. Summary and conclusions In this paper we present a multiwavelength study of the Be/X-ray binary system V 0332+53 with the main goal of studying its transient behaviour during its intermediate luminosity X-ray outburst in 2008. After being yr in quiescence in X-rays, the system underwent a new active period. A new X-ray outburst was detected around 17 October 2008, roughly six days before the periastron passage of the NS. We note that the optical companion entered the brightening state nearly