  New and archived observations of VW Hyi in outburst show the occasional
presence of optical Dwarf Nova Oscillations (DNOs) over the range of 18 - 40 s.
There is a rapid increase in period near the end of outburst, at the same time
that the EUV falls almost to zero, which we attribute to propellering. The DNOs
return to a shorter period after this phase, but are very incoherent. The DNOs
show some modulation by the Quasi-Periodic Oscillations (QPOs) that are also
occasionally present in the light curve. We interpret the QPOs as a prograde
travelling wave in the inner disc, which obscures and/or reprocesses radiation
from the central region. The model is applied to observations of OY Car and WZ
Sge.
