  We present further evidence of the presence of acoustic oscillations on the
slowly-rotating, over-active G8 sub-giant EK Eri. This star was observed with
the 1-m Hertzsprung SONG telescope, at the Observatorio del Teide for two
different runs of 8 and 13 nights, respectively, and separated by about a year.
We determined a significant excess of power around $\nu_\mathrm{max} = 253 \pm
3\,\mu$Hz in the first observing run and we were able to determine the large
separation $\Delta\nu = 16.43 \pm 0.22\,\mu$Hz. No significant excess of power
was instead detected in a subsequent SONG observing season, as also supported
by our analysis of the simultaneous TESS photometric observations. We propose a
new amplitude-luminosity relation in order to account for the missing power in
the power spectrum. Based on the evolutionary stage of this object we argue
that standard $\alpha^2\Omega$ dynamo cannot be excluded as a possible origin
for the observed magnetic field.
