Chromecast Video or ULTRA (HDMI output) sample rate support

Audio Gear Talk
1

Hey all

Is anyone using a HDMI-to-TOSlink audio extractor with a Chromecast ULTRA or Chromecast Video (HMDI), to get 192kHz audio via optical output?

Something like this:
https://www.lindy.com.au/4k-hdmi-audio-extractor-with-hdmi-pass-through

If anyone has it working for 192kHz audio, can you share the brand of HDMI audio extractor that works for you and where you got it?

Cheers!

Edit: apologies. Found out below that Google’s Chromecast and Ultra (HDMI outputs) are limited to 48kHz.

2

No Chromecast supports greater than 96 kHz sample rates – and most are limited to 48 kHz. Unless >96 kHz sample rate support was part of the Chromecast grouped audio update news yesterday.

AJ

3

Crikey! Not sure why my (bad) memory thought the Chromecast Ultra and Video could do 192kHz via their HDMI output.

Have you got one of those yourself and have tested?

4

I probably should have checked this first, rather than rely on my poor memory.

https://developers.google.com/cast/docs/media

5

I’m not aware of any Chromecast devices with HDMI outputs that are capable of >48kHz sample rates.

6

Oh thanks allan - it’s even worse than I thought.

So Chromecast Audio’s TOSlink output is the only Chromecast device that supports 96kHz?

For the Google Chromecast Ultra, is this published publicly?

This link mentions “FLAC (up to 96kHz/24-bit)” and there’s no mention of 48kHz anywhere on the page:

https://developers.google.com/cast/docs/media

7

In the SDK, Chromecast devices report a list of capabilities via this enumeration:
https://developers.google.com/cast/docs/reference/caf_receiver/cast.framework.system#.DeviceCapabilities

The HI_RES_AUDIO_SUPPORTED flag indicates support for up to 24/96; everything else only goes to 24/48. We use this flag to determine device capabilities and what format to stream to the device.

As far as I know, the CCA is the only Chromecast device manufactured by Google that reports this flag, though it’s possible the Home Max might also report it (it wasn’t yet available when were writing our Chromecast implementation and I don’t have one to test with). There are also various Chromecast implementations in third-party smart speakers and streaming devices that report the hi-res flag.

1 Like
8

Thanks Allan!

9

Roon core outputs PCM or DSD, not FLAC. So, maybe that FLAC 96 kHz capability is not relevant. Unless Roon has changed this PCM/DSD policy under the hood for Chromecast.

AJ

10

Noted, it was moreso the sample rate support mentioned (96kHz) that caught my eye on that Google Developer link, moreso than the FLAC mentioned. And no mention of 48kHz anywhere on the page.

Anyway it’s all good now - I’ll stick with a Chromecast Audio for 96kHz support.

I’ve edited my opening post, so I don’t confuse anyone (hopefully) into thinking 96kHz (or 192kHz) is supported by Google’s HDMI output devices.

11

Give Chromecast Audio a try. But many of us have had chronic issues with audio dropouts on 24 bit and/or 96 kHz via the TOSLINK output.

AJ

12

Dropouts over WiFi or using ethernet to CCA? Google have their own power adapter with ethernet, which I might give a try.

https://store.google.com/product/ethernet_adapter_for_chromecast

13

Sean, you really need to read the longstanding Chromecast threads. This is the second Chromecast thread newly created today. Yet, these questions/issues already have been hashed out in earlier posts.

AJ

14

Appreciate your help.

15

Unfortunately, the 96kHz over toslink dropout issue seems to be a CCA firmware problem that we have no control over. Google has been aware of it since at least July, but it doesn’t look like they’re in a hurry to fix it:
https://productforums.google.com/forum/#!topic/chromecast/MdzpFrdAeHk

1 Like
16

https://www.computeraudiophile.com/forums/topic/46611-official-qobuz-issues-thread/?do=findComment&comment=899572

1 Like
17

I got a call from Google yesterday - one of their upper tier teams…

They asked me if I’d factory reset my unit.

I asked them if anyone there had read that thread you linked and if Google had been able to reproduce the issue with 96kHz audio.

They said their team has tested with YouTube’s premium streaming service and had not been able to reproduce the issue so far… :upside_down_face: :man_facepalming:

Anyway, Qobuz have been pro-active behind the scenes it seems. A classic case of the left hand not talking to the right hand at Google :slight_smile:

18

Hi allan

I assume Roon must have at least one contact at Google, since Roon supports playing to Chromecast devices. I assume somebody at Google must have approved something to allow this for Roon.

Has Roon reported the 96kHz stuttering issue directly to this Google contact? If so, have they confirmed they are able to reproduce/replicate the issue at their end?