The instruction do say the AV2 phono are input sockets so you cannot use these. Connecting audio equipment are via the Digital audio connector or via HDMI not sure how the HDMI work.
You could try a 3.5 to phono connector and connect from your head phone socket. Depending if the scart socket is a two way you could try a scart to phone connector.
You could also try contacting Panasonic CLICK HERE you never know some one may have the knowledge to help.