Expert: Wayne Tapia - 1/2/2009

Question
Dear Wayne,
I've been searching for an answer and I came across your site and from your answers you gave you truly are an expert which I'm looking for and will appreciate.  I hope you can help me out.
Current setup:
Dell Inspiron 1525 with SigmaTel HD audio and Vista home basic, connected to TV via HDMI 1.3a
TV is Panasonic Vierra TH42PZ80U connected to HTIB via Optical for sound
HTIB is Panasonic SC-PT760 with Dolby and Dolby Prologic II
Current situation is that I get video from laptop to TV and sound from laptop to TV to HTIB to speakers successfully.  I was told by two different persons that the audio from the TV is passthrough.  That is, it gets the HDMI audio and sends it out to optical without converting to the TV's default audio speaker settings which is stereo.
The problem is that no matter where I change the settings (TV, HTIB, laptop sound device, laptop DVD player software sound output options, etc etc), I cannot get true 5.1 sound.  That is, the HTIB plays the sound as stereo, and my rear speakers are quiet.  Only when I turn on Dolby Prologic on my HTIB that my rear speakers begin to produce sound, which I know should not be necessary because when I play the DVD directly from the HTIB DVD player I get 5.1 without using Prologic.
My question to you is that, is there a way to get 5.1 sound out from my laptop?  Of course the assumption is that the TV sound is truly passthrough, because if that information is incorrect, then the problem is not the laptop sound.  Maybe it's something you can verify as well?
Thank you so much.  Really appreciate your time and expertise.
Emil

Answer
On page 38 of the owners manual, it states "When audio from other equipment connected to this unit via HDMI is output using “DIGITAL AUDIO OUT” of this unit, the system switches to 2CH audio."

If you have another digital audio output from your laptop, you may be able to use that, but otherwise it seems you're stuck with 2 channel (stereo) audio.