Channels reversed on DSD playback

Core Machine (Operating system/System info/Roon build number)

Ubuntu 20.04 64-bit VM with Roon Server 1.7 (Built 667)

Network Details (Including networking gear model/manufacturer and if on WiFi/Ethernet)

Running on Ethernet with an HP Procurve switch

Audio Devices (Specify what device you’re using and its connection type - USB/HDMI/etc.)

Software: Roon Bridge on RopieeeXL 2.596 on a Raspberry Pi 3
DAC : Soncoz LA-QXD1 (USB interface is Xmos U208)

Description Of Issue

Left and right channels are reversed on DSD playback. This happens on:

  • DSD playback at native resolution (DSD64)
  • DSD playback upsampled at DSD256 by DSP
  • PCM playback converted to DSD by DSP

All softwares and firmwares are up to date. This is very unfortunate as the sound is phenomenal on both PCM and DSD.

Manually reversing channels by DSP is out of the question because it’s too CPU intensive in DSD format, and is not a real solution.

For now I’m converting back to PCM in DSP.

Could it only be a firmware bug or a slight incompatibility at the driver level? I guess the problem must be corrected by either the DAC manufacturer or the Ropieee creator.

I created a topic too on ASR and sent an email to the manufacturer. None of the DAC users there seem to have this problem, or maybe nobody noticed!

I saw on another topic this maybe a software/kernel issue with some recognition bits.

We’ll see.

I have the same problem and I sent mail to Soncoz
hope it’s just firmware bug

temporary solution: set Roon DSP to upsample everything to DSD256 and swap cables

no, it’s not related to Ropieee.
Same thing happen when it’s connected on a PC comp with both asio or wasapi

I sent a mail to Soncoz too, but they replied me that all was good on their side.

I will sent them a mail linking to this post, explaining that there may be a hardware or a firmware problem.

I choose the opposite solution, convert everything to PCM and be done with it for the time being.

To me they replied that they need more time for testing.
Yes, converting everything to PCM is also good solution (maybe even better)

Or better yet, swap channels in procedural EQ and save that as a preset.

I tried it as a temporary fix. It was too CPU intensive in DSD.

this is not a solution because channels will be reversed for both PCM and DSD.
You can’t reverse channels in procedural EQ only for DSD, right?
and it’s processing intensitive

Well, you’re right about that.
But, that’s where presets come in handy, although you would still need to switch manually.
Understandably, that’s frustrating.
Upsampling everything to the same rate and using procedural EQ to fix it is not an option for you?

Can’t second that, see attached screen shots.
I upsample and use convolution for room correction, but processing is not slowed by swapping channels by procedural EQ.

It is not processing intensive because you are applying procedural EQ on a PCM stream. Try that in DSD and your CPU will be crawling.

It is better, as a temporary solution, to convert DSD to PCM on-the-fly and not PCM to DSD because it is more efficient and channels will already be in good order.

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Alright, got that!

Interesting problem. None of my DSD-capable DACs are connected at the moment, but I’ll dig one up and give this a try later this weekend and report back. I’m curious to know if this is specific to Soncoz, the Linux kernel / driver, or something in R.A.A.T. (unlikely).

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Okay, I gave this a try with my iFi Audio micro iDSD with upsampling to DSD64. Channel identification was correct, so perhaps this is something specific to Soncoz. I’m running VitOS with this kernel:

# uname -nsr
Linux VitOS 4.19.80-1-rt28-ARCH

Here’s the test track and signal path that I used:

Good luck!

Hello @uryupinsk,

This is a known issue with certain USB DAC chipsets. It can only be resolved with a firmware update to the USB receiver in the DAC.



New firmware just came out. I’m going to try it

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It’s all ok now!


All is good now on firmware 5.01 released today by Soncoz.

Thanks all for your help!

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