Issues setting up Panasonic SC-HTE80

[boydzfish]

I have recently bought a Bravia KDL-32WD752 to replace my Samsung TV. I had the old television connected to a Panasonic Home Cinema box SC-HTE80 model using RCA Leads as there was no HDMI available. Of course the Sony has a spare HDMI/ARC connection and I have used this to link to the sound box but I cannot get anything from it, only through the TV speakers. I have cruised the settings and tried various options to no avail but I did wonder if the HDMI cable may not be 'fast' enough - a high speed cable. Is this feasible or are there some settings I can try? The box is connected to the HDMI/ARC connection on the Sony and the TV In one on the Panasonic.

[Marino.Manolo]

In "Sound" > "Advanced Settings"...

Dolby Digital Plus Out: Select [Auto] to
pass through Dolby Digital Plus
stream to ARC when Dolby Digital
Plus is available through connected
Audio System.
During Dolby Digital Plus stream is
output, Digital Audio Out (optical)* is
muted.
Select [Off] to convert Dolby Digital
Plus stream to Dolby Digital for both
ARC (Audio system) and Digital Audio
Out (optical).

Manolo