No sound from "Kawai PN80" 88 key Weighted Digital Piano

by eddy bourjolly
(brooklyn ny, us)

There is no sound whatsoever coming from my Kawai PN80 piano although the power light and the instrument panel ones work...so that rules out the adapter.

Besides, the piano is hardly moved!

Could it be an internal battery of some sort that needs replacing on my Kawai pn80 piano?

Thanks for your help and suggestions-
eb