  We report magnetotransport measurements on bilayer GaAs hole systems with
unequal hole concentrations in the two layers. At magnetic fields where one
layer is in the integer quantum Hall state and the other has bulk extended
states at the Fermi energy, the longitudinal and Hall resistances of the latter
are hysteretic, in agreement with previous measurements. For a fixed magnetic
field inside this region and at low temperatures ($T\le$ 350 mK), the time
evolutions of the longitudinal and Hall resistances show pronounced jumps
followed by slow relaxations, with no end to the sequence of jumps. Our
measurements demonstrate that the jumps occur simultaneously in pairs of
contacts 170 $\mu$m apart, and appear to involve changes in the charge
configuration of the bilayer. In addition, the jumps can occur with either
random or regular periods, excluding thermal fluctuations as a possible origin
for the jumps. Finally, while remaining at a fixed field, we warm the sample to
above 350 mK, where the jumps disappear. Upon recooling the sample below this
temperature, the jumps reappear, indicating that the jumps do not result from
nearly dissipationless eddy currents either.
