M1 how to output multichannel audio HDMI to TV

[Platform]

Hi

I have been using my M1 Mac mini with an AVR as a HTPC, and got multichannel audio output to enjoy some surround sound while watching movies.

Mac mini HDMI output - AVR HDMI input
AVR HDMI output - TV eARC HDMI input

This way I got MIDI setup to recognise my AVR and it "saw" multichannel (5.1) as an output option I could select.

However I have now sold my AVR and using a Sonos setup (Arc, sub, 2x SL)
Mac mini HDMI output - TV HDMI input
Sonos Arc HDMI input - TV HDMI eARC

But I am unable to get the MIDI setup to "see" anything else then 2 channel stereo??
Anyone have any tips on how I can set the Mac mini to output multichannel audio so my Sonos system is able to reproduce surround sound from the media I have access to via my Mac mini (I have my movie library .h264/h265 attached via a large storage solution to my Mac mini so I don't have to swap blue rays etc)

 

[agentbob]

Did you find a solution to this? I'm trying to get my m1 macbook air to show 5.1/6 channels of my vizio soundbar and nothing seems to work... I've tried HDMI arc passthru and also direct optical cable through a caldigit ts3 usb c hub but the Audio MIDI Setup only ever shows 2 channels =\

 

[rafavcc]

Hello. Did you find a solution? I guess it has to do with Apple not allowing passthrough using any ports. Thats a shame.

 

[sneeks]

Same issue here. Mac Mini connected to my TV via HDMI and my Sonos Beam connected to the TV via HDMI ARC. The Mac only shows me options for 2 channel output.

 

[shaun.au]

Anyone?

I love finding a thread for the exact issue I'm researching... and then despair that nobody's posted a fix

 

[yOr3z]

Hi guys,

Not the type of guy replying of forum's topic, but having an account here and appreciating help from ze internet, here is my take.

I got the same issue when only 2 outs channel stereo were showing on my Audio Midi Setup.

Fix for me: changing the HDMI audio input parameter on my LG CX TV to Bitstream (previously on PCM).

Hoping you guys have something similar and can sort it out,

Cheers

 

[Pauliepaul4321]

I like yOr3z's reply.
On my Samsung TV I changed the HDMI output to DTS. My Onkyo receiver picked up on that, so now I have 5.1.
Which is better than stereo at least.

 

[averagejim]

Why would changing the HDMI output to DTS on your TV make a difference? The multichannel signal goes from the computer to to the AV recveiver.

 

[averagejim]

Did you find a solution to this? I'm trying to get my m1 macbook air to show 5.1/6 channels of my vizio soundbar and nothing seems to work... I've tried HDMI arc passthru and also direct optical cable through a caldigit ts3 usb c hub but the Audio MIDI Setup only ever shows 2 channels =\

Did you get a solution? I was considering buying a macbook air m1/2. I listen to multichannel audio through a yamaha AV receiver. My PC does it but the fans are a distraction

 

[Kontikonsumi]

I saw that the mbp M1 does not support "HDMI multichannel audio output", but versions from mpb m2 on do. What is this feature good for?

 

[westonagreene]

From my research for USB to TOSLINK, which may help with HDMI:
"""
Apple MIDI won't recognize more than 2 channels when plugged directly into a TV or via USB to TOSLINK (Optical Audio). No Apple apps will.
Being more explicit:
Mac > USB-C to TOSLINK adapter > Fiber optic cable > TV = only 2 MIDI channels
(the adapter used: https://www.amazon.com/gp/product/B09QFYNB7Y)

The only option is to use a third party app, like VLC.

For VLC: in menu bar: Audio > Audio Device > "USB SPDIF Adapter (Encoded Output)"
(The "(Encoded Output)" part is the key.)

I used this guy's test audio files, specifically the `DTS 5.1.wav`: https://www.reddit.com/r/hometheater/comments/11qqv95
From my research, appears as though the only way to get Apple apps (like MIDI) to recognize the distinct speaker channels is to connect HDMI directly to an Audio Receiver. (And this is only for recent Macs; appears as though TOSLINK (optical audio) was better supported in the past.)

(In my case, my Samsung TV had to be in "HDMI Audio Format", "Bitstream", not "PCM"; and then "Audio Format" of "DTS Neo 2.5" (not PCM).)
"""

When I repeated these steps with an HDMI cable (Mac > HDMI cable > TV = only 2 MIDI channels), the "(Encoded Output)" actually has no audio, but I'm posting here regardless because I suspect that something about my TV or Receiver or configuration might be the problem.