After a lot of investigation I found that some units have a 1.5-2.0 volt AC signal (sounds like a 60Hz signal i.e. hum) between the neutral side of the interconnect and the earth at the power bar.
Williewonka 06-24-10:
between the neutral side of the interconnect and the earth at the power bar.
Williewonka,
Not sure what test you preformed.... Can you be more specific. What do you mean by "neutral side of the interconnect"?
Lifting the ground makes the amp hum more
06-25-10: Williewonka
Are you sure the sound you are hearing is a hum and not a buzz. Does the noise vary when changing the volume level?
I just purchased a NAIM integrated amp and I am experiencing a hum but only from the DVD player.
06-24-10: Williewonka
I would try what Al said in his post. Could be a bad interconnect. Could be a bad signal ground solder connection inside the DVD player.
Does the hum/buzz change if you put your hand on the metal case of the DVD player?
I would also try another set of line-input jacks on the NAIM.