[3DBuff]

Here is my 2 cents experience with audio extractors for some other people interested in this topic.

I have old high current 7.1 receiver from DVD days - no HDMI ports.
I wanted to see if I could get 7.1 extractor to work with my Pi.

First model with 3.5mm analog line out jacks was a complete failure
http://www.mcmelectronics.com/product/33...ApzC8P8HAQ
Similar units are sold all around probably made by Bytecc.
Two of those units burned on power up within a second after connected to my Epson projector. I found review on Newegg describing the same issue with Toshiba projector. Maybe this thing works with DVI computer screens with HDMI adapters only.

Second model with RCA jacks line out recently purchased from Ebay:
http://www.ebay.ca/itm/361336868944?_trk...EBIDX%3AIT

My first impression is very good. First of all it didn't burn on start up!
Switch set to multi channel and I get full control over audio from Kodi audio setup screen.
When Kodi -> System -> Audo - Number of channels is set to 2 ch. and no pass through I get 2 channels stereo for headphones amp. separate from main receiver. Changing this to 7.1 I get LPCM audio on all channels. Setting it back to 2 channels and enable pass through I get DD and DTS over optical SPDIF.
This works very well with Pi and as intended. Sound is clean with no distortion or any noticeable noise.

I hope this helps and saves time for others looking for similar setup.

[elektrinis]

I have a very similar splitter, just for 5.1 and extra vga out. But otherwise identical.
Unfortunately, when set to 5.1 and passthrough disabled, I only get stereo and subwoofer.
I am running Kodi 16.1, as newer ones dont run on Nadroid 4.4.4, that I have in projector wowoto H8. Same results o windows 10 machine.
I was fiddling around for a whole weekend and could not get it working. Very frustrating and a tragic experience so far.

[3DBuff]

Every device may be a little different but in general for the extractor to work on analog jacks you need to set Kodi > setup > audio to HDMI device and select 5.1 or 7.1 below for Number of channels. As long as extractor is set for 5.1 or 7.1 PCM you should get all individual channels on analogue output.

If you are trying to use optical or digital coax cable you need to set the Audio Channels to 2.0 only and "Allow Passthrough ON" in Kodi audio. Always use HDMI for "Audio Output Device".

Check your receiver settings. It's unusual to get sub out if you don't have full 5.1 on analogue channel input. The sub works only if you have stereo signal and the receiver is doing sound processing. Receiver needs to be set for "Multi-channel" analogue or something similar.

[elektrinis]

Thank you for replying. I set Kodi to HDMI output, 5.1 channels, Optimized, passthrough off. My amp is connected to analogue RCA connectors. The amp is actually a DIY class-D analogue amp, has no mind of it's own, so I'm sure it does not make up extra sounds.
The weird thing is that I get full range stereo on front L/R speakers and a subwoofer. However surround and Center speakers are completely silent. 5.1/2.0/pass switch on the extractor has no effect.
OS: Windows 10. Under windows audio devices, it shows up as stereo device. Not sure if this is a problem or not.
If I enable passthrough and try to use toslink output to a capable receiver, I get silence for 5.1 streams, however stereo streams and GUI sounds work fine in PCM mode.
Will continue this battle and report back, if I succeed.

[3DBuff]

When you select 5.1 switch on your extractor do a reset button if you have any on this device or power up.
If this is HDMI switch with multiple in and out unplug everything and use only HDMI 1 input and HDMI 1 output for testing.

It's difficult to point the problem across multiple hardware platforms. This could be something with extractor or your player device (projector with Kodi). I wouldn't trust Windows for testing as well unless you had it working with some other system. You need to check each component individually. Amp is very simple. If you insert paper clip into each RCA line in socket you should hear buzzing sound from each channel, one at the time. Extractor is a bit difficult. You would need to test it with working system maybe someone you know that has working Kodi system with amp. The same apply to projector with build in player. Projector is probably at fault from everything you said. You could try Raspberry Pi 2 or 3 board as player. It works very well, it's inexpensive and easy to set up on LibreELEC. Blu-Ray player with HDMI output is another option to test the extractor.

[elektrinis]

I was looking in to using RPi3, but would like to find a ready to use solution, with nice case (not acrylic laser cut DIY one), power supply, IOs etc, as I am too old and too busy to do it myself. I mean, I am a decent engineer, but I also have life, and lately bit too much of it. I did find a couple of options, but they were much more expensive, close or over proper android box.

At first I bought this LED projector (Wowoto H8) with android and S/PDIF output, expecting to get a nice and clean solution without too many boxes. This projector can even be used as a media device with screen switched off, which is really handy to listen to radio or private music collection, if controlled from Yatse app on your phone. However it totally failed to output proper 5.1 DD/dts audio via S/PDIF, I only get digital noise in PCM format. Likely there are extra volume control layers on top of "passthrough" and it totally bricks the data. This is a complete deal breaker for me.

Then I thought ok, I'll use the projector as slave device with HDMI. I have an old windows tablet, DELL ST2e, which I decided to hang on a wall as a media controller with Kodi web interface in full screen, and Kodi being run on secondary display, which is a projector on HDMI. Everything works well, however, once again,  I am unable to extract that damn 5.1 audio... Actually the only way I was able to do that was with external audio card USB->optical (Turtle beach advantage 2), which comes with proper drivers. But that's too many cables and boxes to hang on a wall. Will keep battling this extractor thing, but I'm lost for now.

[ActionA]

The OSMC Vero 4k might interest you.

[elektrinis]

I also have a Fire TV box 2nd gen, which I got due to it having optical out.
Works really well for the price, however I am very annoyed by Amazon part of it. Also a huge problem to me is volume control, or simply lack of it. I use a simple analogue amp, so I cant adjust volume without walking to it. This means I have to get a new amp, fiddle around with several remotes all the time and, the worst of all, try to explain to my family which button does what and why.

OSMC has volume buttons on the remote. Can it actually adjust volume with 5.1 out? I need to know this for certain, I dont want to boy one more box just to test....

[Sam.Nazarko]

If you're passing through audio, it won't do anything.

If you enabled 7.1 and disabled all passthrough formats, you'd get 7.1 out, but it wouldn't show as passthrough on your receiver. This would let you control volume from Kodi.

Looked in to the possibility of controlling volume via CEC. In theory this is in Kodi already, but it doesn't seem to work properly and seems only TVs can be controlled via this method reliably. I will revisit this when I have some spare time.

I see you'd be using SPDIF. SPDIF will only give you 2 channels unless you use AC3/DTS. You should be able to use AC3 transcoding and set channels to 2.0. This would let you set volume on non AC3 tracks; but I still believe AC3 would just be passed through, and Kodi would not be able to control the volume. If you can get audio out from HDMI on the Vero 4K and not rely on the optical port, things are a lot easier.