First world problems, I know, but Netflix does not have surround sound in the Model 3. Just stereo. Sounds great, but I wish it were actual surround.
What model I have the LR AWD and last week while waiting on the kids I was watching a movie and I had different sounds on the left right as well as rear left and right. Example motorcycle zooming by went from front left to rear left seemed like surround sound to me.
There did seem to be a discrete channel going to the subwoofer. Or else they have a good cutover in place. I couldn't tell about surround sound, but I did notice that front was stereo, not 3 discrete channels. Normally with surround sound, you'd get voices in center speaker and left and right channels would have soundtrack/sound effect type info. But in the car, voices were mixed in with soundtrack/sound effects in left and right channels. So, hopefully down the road, they'll implement true 5.1 surround sound as they obviously have enough speakers to do it and have descrete channels going to each speaker since the farting app targets front right, front left, rear right, and rear right distinctly.
You can confirm this by using the netflix audio options. On systems that support surround the options will be usually 5.1 by default and a version without any numbers which is just stereo. In Tesla, it's only the regular option (English, Spanish, etc)
Tesla offers a Dolby ProLogic Surround option with the Ultra system to convert stereo source maternal into surround sound on MCU1 equipped cars. You can use it with Netflix or Nova (https://novatvapp.com) The general opinion is this distorts music more than it helps, and should be left off. A software improvements was made in late 2017 that improved the quality, such that some owners now like the option. The system only supports stereo source material. For example, FLAC files supports up to 8 channels, but only 1-2 channel mono/stereo files can be used from USB files
To clarify, model 3 does not use a Dolby system.