Panasonic TX-32DK2 32" widescreen TV: no sound from lef

[markofealing]

1. Noticed the other day that there is no sound from the left speaker.
The TV has at the back a RCA Right/ Left front speaker audio out to
connect to a amp if you wanted to use alternate front speakers, the
output volume level is controlled by the TV's volume control. (note it
is not a balance issue!). I've tried this connection to an amp and I
get both let and right channels so I assume the connection from
internal amp is functional. I think the problem is probably a wire
which has come adrift either from the speaker or from the board.
However, could it be something else?

2. When the screen is not displaying any image i.e. a black image there
is a red tint to the black. O this model of TV is it possible to adjust
this out via the Service Menu and if so what are the settings?
Alternative are there any manual settings on the board? Note: There is
no RGB adjustment from the TV's Picture menu.