192khz 24bit sound issues (specific hardware within)

Connected Audio Devices

NAD D 3045 amp (asynchronous usb input)

Raspberry Pi 4 running latest RoPieeeXL

Qobuz subscription and my own library of lossless FLAC and ALAC files

Roon core is running from Windows 10 pc (Lenovo x270)

Description of Issue

When streaming 192khz 24bit FLAC files from Qobuz or playing directly from a 192khz 24bit FLAC file on my harddrive my setup produces a distorted, garbled output. The music is tinny, sounds compressed, robotic, and just broken.

If I tweak settings in Roon to limit output to 92khz or I use DSP to convert sample rate of 192khz to 176.4khz then the problem goes away and the music sounds fine again.

How can I debug this issue? Is it something to do with my NAD amp and its usb input, or a combo with the raspberry pi?

It’s not a huge issue as 192khz files are relatively rare, but something is definitely wrong and I want to find out what.

Thanks

A Pi 4 running Ropiee normally has no issues playing 192k and higher. The D3045 is specified up to 192/24 via USB so assuming other 192k sources sound OK I’d eliminate the cable as a potential problem. So…
Try USB direct from the core.
Try another source.
Try another cable.

I tried a few different options. The cable makes no difference, so I moved to my PC (where the Roon core is installed). 192khz asynchronous usb output from pc into my NAD works perfectly.

So… This seems to be a raspberry pi 4 or maybe RoPieeeXL issue.

What could be causing the problem?? I have updated my raspberry pi 4 to latest firmware and ropieeeXL is also latest version.

Hi @therourke

I took a look at the D3045’s manual, and I notice that Windows and macOS are mentioned, but I don’t see anything about Linux support:

image

This device might not be fully compatible with Linux, which is why you’d have that problem with a Pi and not Windows. I’d reach out to NAD and ask if they can clarify whether or not Linux is fully supported and if this should work.

I notice that Volumio says it supports the NAD D 3045 explicitly, but suggests an ethernet driver update, here: USB DAC compatibility List - #180 by WvdG - Compatibility Lists - Volumio

Does this shed any light on this issue perhaps? I am going to try Volumio tomorrow and see if it has the same issues as ropieee.

I installed and ran Volumio on my raspberry pi 4. This seemed to have solved the issue… but then after playing a few files the problem kicked back in.

Arghhhh

Hi @therourke, I’m sorry I missed your update. Are you still seeing issues here? Have you tried reaching out to NAD about this?

Yeah, NAD said this:

“Perhaps the Raspberry Pi is not able to keep up with the High Res data stream. Do you have other devices with a USB Input you can use to test the Raspberry with another device?”

I need to try the asynchronous out on the pi with something else, but I don’t have anything at the moment.

I don’t think their answer solves the issue though, really.

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Thanks for the update, @therourke. I agree that it would be an interesting test — If other devices are working okay in that setup, it would definitely prove that it’s specific to the NAD.

Having run RPi 4 and 3B+ with Ropieee in the past and currently with DietPi, while upsampling to 705.6/768kHz/32bit or DSD512 over 5GHz wireless without any of the reported problems on a S.M.S.L. M300MkII debunks that NAD representative as being clueless.
It must have more to do with a network bottleneck and/or a USB driver incompatibility…

Yeah. I didn’t take much from the NAD response either.

I doubt very much it is a network bottleneck. I have ethernet running at 110mbps.

USB driver compatibility sounds possible. I updated my pi to latest firmware and drivers. Weird how it stops working at exactly 192khz on the dot. Everything below this is absolutely fine.

As I say above, I can run 192khz perfectly straight from a Windows PC.

A late update to this. I have come to terms with downsampling everything 192khz or over to 176khz. I have been using the Volumio Roon implementation on my Raspberry Pi 4 and it works great.

Recently I tried DietPI for a few reasons. It seems to work well. BUT I now get the exact same problems I outline above, but for anything over 92khz. Volumio doesn’t work over 176 and DietPi over 92 (with my NAD).

What is happening?

I don’t use a NAD, but I have two RPi4’s both running RoPieeeXL and they play 192/24 using USB out to my DAC’s with no problems.