Originally Posted by jestermx6
doesn't that change my audio to stereo? kind of defeats the whole purpose of having a receiver...
I pointed out multiple times during my Vizio support chat that I, theoretically, would have to give up Dolby Digital 5.1 surround sound to implement their L-PCM "fix", and that Vizio's alleged switch to support only L-PCM audio (typically only two-channel stereo), at the expense of six-channel Dolby Digital, on their newer TVs did not make any logical sense. However, the Vizio support representative conveniently changed the subject and never directly acknowledged either of these observations when I brought them up.
Technically, you can still have Dolby Digital after switching your cable box to L-PCM, although it can create some convenience problems, and does not necessarily even fix the sync issue. The L-PCM setting (at least on Time Warner Cable Motorola boxes) only changes the audio type going out of the cable box's HDMI output. Dolby Digital is still carried by the separate optical digital audio output on the cable box. So, you can connect the cable box directly to the TV via HDMI (now carrying the L-PCM audio signal that apparently is less likely to "confuse" a Vizio TV than Dolby Digital), and then connect the cable box to an AV receiver via optical output (audio only). Then, you just turn the TV speakers off.
...the receiver shoudln't be feeding any audio to the TV AFAIK. I'm using all HDMI. The receiver handles all audio, and feeds video to the TV through a single video output via hdmi. Thinking back, i believe the TV is somehow to blame because I had this setup with my old Panasonic 44" DLP up until I bought this TV, and everything was in perfect sync...
I am not sure whether your receiver is removing the audio or still passing it through the HDMI cable to your TV. Have you tried using the TV speakers with your setup? If it is passing Dolby Digital audio through to your TV, perhaps your TV is trying to process it, even though you are not playing it through the TV speakers.
The more interesting test might be the component video test. Obviously, you don't have to try that, but if you can hook your receiver up to the TV through component, you know there is no audio being carried, and you also don't have the other issues associated with digital video (e.g., handshaking/digital rights management). Frankly, my eye is not keen enough to detect any difference in 720p or 1080i carried by component vs. HDMI. I don't think component can handle 1080p, and it is possible that some PS3 games may not be quite as good at 1080i, but it would just be a temporary test.