Roon forcing bit-depth downgrade from 24bit to 16bit on Xonar STX in windows 11

[Satyajit_Dey]

Roon Server Machine

OS: Windows 11 22H2 OS build 22621.2715
CPU: Core i3-8100T CPU @ 3.10GHz Dell Mini PC
RAM: 8 GB

Networking Gear & Setup Details

ASUS RT-AC68U Router
Roon Core attached physically to the Router
VPN: Tailscale for Roon ARC only

Connected Audio Devices

1. Roon Core connected to via USB to ifi Zen One Signature DAC which is connected to AMP/Speaker.
2. Gaming PC having Xonar STX soundcard which is connected to a Headphone Amp via RCA and also to the same AMP/Speaker as the core. I switch the output devices as desired.

Number of Tracks in Library

Albums: 378
Tracks: 5389

Description of Issue

I was using my Asus Xonar STX Card on my PC and it was working fine on Windows 10 but after switching to Windows 11 I don’t get the option to set Max bit per sample (PCM) anymore. The option is simply gone. and now every time the song’s bit rate is higher than 16bit it is downgrading it to 24bit. I have tried reinstalling the driver and also tried other Uni drivers for Xonar STX nothing seems to work. Previously default Asus Windows driver for Windows 10 use to work just fine on Windows 10. Also there is no official Windows 11 Driver for Xonar STX card so am using the Windows 10 64 bit version on Windows 11.

I have another system with Windows 11 which is the Roon core, attached to ifi zen one signature DAC and it has the option to set max bit depth and all and it is working fine there.

Any help is welcomed.

[Robert_F (Rob)]

@Satyajit_Dey, welcome to the Community. I don’t have a Xonar ST, but have you tried seeing if you can set the bit depth and sample rate by going into the W11 Control Panel and see what options exist for the Xonar under Sound? This is not the Windows 11 Settings menu, but the legacy Control Panel app? Also, while it is not visible in your screenshot, is your Xonar set to Exclusive mode in Roon?

[Satyajit_Dey]

Thanks for the reply. Sorry I forgot to mention this in my main post.

Yes… This is the first thing I did before messing with anything to solve the issue. Here are the screenshots.

I have set both in classic control panel and in windows 11 sound settings. Also found that changing in the windows 11 sound settings also changes the settings in the classic control panel sound settings.

[wklie (Peter Lie)]

1. Is there a 32-bit option in the driver properties instead of 24-bit?

2. Is there a WASAPI driver you can try instead of ASIO?

[Robert_F (Rob)]

I don’t believe you mentioned it, but is the Xonar set to Exclusive mode in the Roon Settings tab?

[Satyajit_Dey]

1. There is no 32bit option for Xonar STX cause it supports upto 24bit 192khz.
   

   

2. There is WASAPI option but when I play through it the light is green.
   

   

[Satyajit_Dey]

1. I didn’t find the Exclusive mode option for Xonar STX in AISO mode.

2. I did enable the WASAPI mode for Xonar STX and I found the Exclusive mode option and turned it on. Now it worked.
   
   

Now the thing is why can’t I find this option for AISO mode in windows 11? If I use WASAPI will I be losing out vs AISO mode in terms of sound quality/performance?

[Satyajit_Dey]

Issue Resolved…

I broke the full post into parts…

Part 1:

After all your suggestions and successful workaround for WASAPI mode I started searching for AISO related setup options and stumbled upon something that solved the issue.

The problem lies with the default ASIO bit rate set by windows 11 after installing the Xonar STX drivers in windows 11. As there were no option in the Xonar control panel to set the bit rate for AISO I stumbled upon a small module “asioconfig.exe” in the [UNi Xonar Drivers 1.81] (UNi Xonar Drivers official page) page, as I was trying to use UNi Xonar drivers instead of official ASUS drivers previously to solve this issue.

I downloaded and ran the “asioconfig.exe” file and wala… the AISO bit rate was set to 16bit by default.

I quickly changed it to 24bit and applied.

Immediately went to roon and ran a song and finally it ran perfectly.
(I turned on a few EQ and volume normalisation options after it ran smoothly so that is why the screenshot has those shown in the processing part)

[Satyajit_Dey]

Part 2:

Then I went into the settings for Xonar STX ASIO and found that the option for setting the bit rate and more options like MQA, DSD, etc. also showed up along with the option to change bit rate just as it was in Windows 10.

Previously before issue was resolved, bit rate was not showing (for reference):

I dont know how the “asioconfig.exe” fixed the issue and let roon get the proper ASIO info from the Xonar STX device but it worked for me.

I hope this will be useful for others.