iPod dock picking up interference from iPod

[snadge]

My partner has just bought a iPod Docking Station for £40 - it was reduced from £80 at Tesco's

out of box it was clear it was a return as there was slight marks/scratches....

it has 2 x 10w speakers and a 20w bass speaker in middle....

now, the problem is when the backlight is on (on the nano) and the ipod nano is changing anything on screen it cackles and stuff as if its picking up interference from the ipod? now it ONLY happens whilst the backlight is on - when the backlight goes off and it still changing the time and name on screen it DOESNT make the noise...(which can only be heard in silence or low sound) - once you choose and album and let it play its fine but they (Tesco) have none left and you cant get any as near as powerfull for same price so we are looking for a fix if anyone can help....

its fine when my mobile phone is plugged into it via AUX proving its picking up from the iPod ONLY when backlight is lit...

is there anyway of preventing this?

thanks

[Krispy Kritter]

I would test with a different iPod first. It could be an iPod issue, and not the dock.

[snadge]

its the dock - it changes , sometimes it keeps doing it when the backlight is off - the only way to completely avoid it is plug in via 3.5mm jack but then the remote only works for volume and on/off weve tried everything even turning off all hardware and wifi and its still does it