Sound bleed-through on Panasonic TV

I have a 28" Widescreen Panasonic TV, model: TX-W28D2DP

Never used to have any problems with it, but since moving house I now
notice that I get a very faint, tinny sound bleed-through from
whatever channel the TV was set to before I started playing the DVD,
ie the sound of the TV channel can be faintly heard in the background
while watching a DVD.

The DVD player is, as always, connected to the TV via the RGB SCART
socket.

I can work around the problem by switching to channel 0 (ie the VCR)
before I start playing the DVD (the VCR must be off of course) but if
I'm taping something I then of course get the problem back.

Think I'm going to try and 'de-tune' a channel so I get nothing at all
and switch to that before playing DVDs if I'm taping anything - thing
is, it's just another work around.

Anyone got any ideas as to a possible cause (and fix) please?


The only thing that has changed (besides the location) is that I
needed to do an auto-tune to re-tune the channels when I moved.



Thanks