Reddit reviews Battlestar Galactica - Season 4.0

ELIA(dult):

Stereo

If we assume you're listening in stereo, there are two distinct channels of audio: Left and Right. Dialogue, music, and effects come out of both speakers.

Your computer/tv has no way to remove a "section" (just the dialog, for instance) of the audio without seriously effecting the remaining sections. Imagine you wanted to remove just the kick/bass drum from a song with your car stereo. You could turn the bass knob down, but that would affect the bass guitar as well (or tuba, double basses, synth bass, or the big jug in Hillbilly Bob's All Jug and Tambourine Band or whatever crazy shit you're in to). Your computer/tv suffer from the same limitations.

>But /u/Sysop_2400! My cousin has this Karaoke machine that can remove vocals from songs.

Press play on this Buffalo Springfield song from the early days of stereo and carry on reading:

Think of the left channel and the right channel as completely separate audio streams. In general, sounds aren't panned as "hard" left or right as they are in our example song. The sound usually exists in both channels. A sound that is panned to the left will be louder in the left channel (and thus the left speaker) than it is in the right.

Some sounds are equal in both channels. They sound like they're right in the center. Using a bit of magic, you can subtract one channel from the other^1. Sounds that are equal in both channels (panned dead center) will completely disappear. Anything panned (even a little bit) left or right will not go away completely. The volume of anything panned all the way left or right will remain unchanged.

In most modern music, vocals are panned dead center, thus, are able to be removed with this little trick. The downside is, anything else in the song panned dead center is gotten rid of also. This is why "vocal remover" magic boxes make the rest of the song sound "weird".

This can happen with TV shows as well (it's exceedingly rare). If something goes terribly wrong somewhere in the file conversion process over at Netflix, your software is having a bad day for some reason, or more than likely one of your wires or connectors is damaged, you may end up with a home brew vocal remover. This would not, however, account for the total removal of dialog, as dialog is generally panned around as the actors move around on screen.

To diagnose: Pan all the way to either side, or better yet, try using only one channel of audio. If it's still just the dialog missing, the problem is not on your end.

5.1 Surround Sound

This is a much simpler situation. Battlestar Galactica has been released in a variety of formats, including Season 4 in Dolby Surround 5.1.

When dialog is mixed for 5.1, depending on the show, episode, or even scene, it may be only in the center channel. Music and sound effects are commonly left/right, and surround left/surround right respectively.

If the audio stream for the center channel is fucked up, you may very well be missing all the dialog while the majority of the rest of the audio sounds fine.

To diagnose: Listen only to your center channel (move your noggin close to it, or unplug the other speakers). If there is no audio at all coming from the center channel, shit's fucked up. If it's only half an episode, the problem is not on your end.

1: Basically, "flip" one channel upside-down so that what was positive is now negative and vice versa. If we flip the left channel (phase invert) and then recombine it with the right channel, the portion of the signal that was equal now cancels itself out (phase cancellation).

source: audio professional for 15 years

Warning: IMDB pages may contain spoilers. For the record, "Faith" is season 4, episode 6. S04E07 is "Guess What's Coming to Dinner".

Tl;DR: Netflix fucked up.