  The Kepler space telescope observed over 15,000 stars for asteroseismic
studies. Of these, 75% of dwarfs (and 8% of giants) were found to show
anomalous behavior: such as suppressed oscillations (low amplitude) or no
oscillations at all. The lack of solar-like oscillations may be a consequence
of multiplicity, due to physical interactions with spectroscopic companions or
due to the dilution of oscillation amplitudes from "wide'" (AO detected;
visual) or spectroscopic companions introducing contaminating flux. We present
a search for stellar companions to 327 of the Kepler asteroseismic sample,
which were expected to display solar-like oscillations. We used direct imaging
with Robo-AO, which can resolve secondary sources at ~0."15, and followed up
detected companions with Keck AO. Directly imaged companion systems with both
separations of $\leq$0."5 and amplitude dilutions >10% all have anomalous
primaries, suggesting these oscillation signals are diluted by a sufficient
amount of excess flux. We also used the high-resolution spectrometer ESPaDOnS
at CFHT to search for spectroscopic binaries. We find tentative evidence for a
higher fraction of spectroscopic binaries with high radial velocity scatter in
anomalous systems, which would be consistent with previous results suggesting
that oscillations are suppressed by tidal interactions in close eclipsing
binaries.
