Have been bought a Sharp HT-DV40H dvd home cinema system and the
subwoofer has a low level hum which is noticable at low level playing,
its a passive subwoofer so no mains transformer in it, at first I
blaimed the subwoofer its self but after plugging another speaker in I
get the same hum.

I do notice that the speaker cable is the bog standard speaker cable
and wonder if I get better cable if it would cure it.

This happens no matter what I am playing be it radio/cd/dvd or through
the optical sky input.
I have now turned all off at the mains apart from the home cinema its
self and it still hums.
When I reduce the volume to 0 it goes when I turn it up above 0 its
back.


Anyone come across the same problem?