Chromecast built-in HiRes downsampling to 48Khz

[Andrew_Landsverk]

Roon Core Machine

VM on Proxmox, 16GB of RAM, 8 CPU cores, 100GB drive

Networking Gear & Setup Details

Full Ubiquiti networking stack

Connected Audio Devices

Anthem MRX 740 8K AV Receiver

Number of Tracks in Library

8000 tracks

Description of Issue

Hello! I’ve been testing the capabilities of my Anthem. When I use the Plexamp app to Chromecast to the anthem with a track like 96/24 or even 192/24 the Anthem reports that it is receiving 96/24 or 192/24 etc.

When I play back the same tracks with Roon pointing to the Anthems Chromecast everything is down sampled to 48khz.

I searched the forums and found a similar thread with no resolution: Supported sample rate of Chromecast builtin - #25 by Rugby

Is there any way to tell Roon what the capabilities of the Anthem truly are?

[Andrew_Landsverk]

Bump, does anyone know how I can make this work? Thanks!

[noris]

Hi @Andrew_Landsverk ,

Apologies for the delay here. Some Chromecasts do support higher sample rates, but the Chromecast device itself would need to announce the high-resolution functionality to us, and we have seen that many do not. We’ve enabled a Chromecast debug mode for your account, can you please perform the following?

• Disable the Anthem zone
• Reboot Roon Core twice to ensure it enables the debug mode
• Re-enable Anthem zone and play something to it
• Access your Roon Core (RoonServer) logs using these instructions and upload a set here:

https://workdrive.zohoexternal.com/collection/8i5239cc05950ac07456889838d9319545a82/external

• Let us know once logs are uploaded

@Andrew_Landsverk

Roon Core Machine

VM on Proxmox

Please also note that VMs are not supported and may complicate the logging a bit. I suspect the error is with the device itself, but the logs would be cleaner if you could reproduce the behavior on a standard, non-vm system.

[Andrew_Landsverk]

Hello!

Thank you for the reply! I have uploaded my logs. I also wanted to mention that I stopped using a VM quite a bit ago, my RoonServer is running on a Mac Studio now

I look forward to your response.

[noris]

Hi @Andrew_Landsverk ,

I spoke to the team regarding this issue, but it looks like this thread closed in the meantime, so I have re-opened it. According to the information we receive from the device, it is telling us that it does not support high-resolution playback capabilities: "hi_res_audio_supported\":false

Debug: [cast/client] [MRX-740-5a001731be06c1a54092251a59a26bb0._googlecast._tcp.local] Received Cast message: { "sourceId": "99851cdb-563d-4a26-a590-058ef8db8c22", "destinationId": "sender-61404", "namespace": "urn:x-cast:com.roonlabs.cast", "payloadUtf8": "{\"type\":\"DEVICE_CAPABILITIES\",\"requestId\":21,\"capabilities\":{\"bluetooth_supported\":true,\"display_context_changed_supported\":false,\"display_supported\":false,\"focus_state_supported\":true,\"hi_res_audio_supported\":false,\"is_group\":false,\"remote_control_input_supported\":false,\"remote_control_overlay_supported\":true,\"sleep_timer_overlay_supported\":true,\"touch_input_supported\":false,\"is_hdr_supported\":false,\"is_dv_supported\":false,\"is_dolby_atmos_supported\":false,\"is_cbcs_supported\":true}}" }

The manufacturer of this device would be in the best position to look into this further and make this change on how the device reports it’s Chromecast capabilities, please reach out directly to them and do let us know what they say, thanks!