1. Yes, all of the inputs will down-convert the audio to 2.0 audio except for the co-ax tuner.
2. The tuner, if used as the cable input or the antenna, will transfer 5.1 audio via optical only.
Does that help?
1) I understand that the Digital Audio Out (Optical) on this model downgrades sound channels from 5.1 to 2.0 when using the HDMI inputs, but what about the Component In 1 and 2? Does 5.1 sound on the Component In come out as 5.1 on the Digital Audio Out?
2) Does the TV pass through 5.1 sound from all inputs to the Audio Out or does it downgrade the sound like the Digital Out (Optical) does with HDMI?
The manual is a bit vague on these issues.
Thanks in advance for your time,