Qutest USB Clicks & Pops

Audio Gear Talk Chord
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I am using an Allo USBridge sig with a DigiOne Sig on top into a Chord Qutest, and I am using Ropieee XL as the endpoint software running in the USBridge. I am also using HQPlayer for upsampling. I have the endpoint set up so I have a choice of either SPDIF Coax or USB into the Qutest (its nice to be able to compare the outputs). The USB input goes to 768khz but I get the occasional white noise (seems to be a known bug with the USB input on the Qutest), so I have put a limit of 705khz in HQP for the USB – this doesn’t matter much as most of my material is 44.1 based. For the coax, the upscaling looks like is limited to 192khz.

I am finding when I use the USB input on the Qutest I get clicks, pops and glitches – more often than not they sound like clicks on an LP record. These are not present when I use the SPDIF coax. I would like to use the USB more as I am finding the upsampling to max frequency does have sound benefits, but the clicks and pops are annoying. Any ideas on causes or fixes for this?

One possible thing I am considering is one of those SRC-DX devices, so I can get max upsampling and use the BNC coax inputs. I have heard good things about this on here and elsewhere but any other experiences would be gratefully received – especially if anyone hears clicks and pops through it. I suspect not, but I would be happy to hear actual experience rather than my own guess.

Thanks for any suggestions

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It looks like you’ve achieved what many think it’s the ultimate goal of a digital stack: to emulate vinyl. :wink:

2 Likes
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Have you tried reducing the USB Upsampling to say 192 and trying that?
If ok then slowly increase the Upsampling until you hit the clicks and pops again.

I did not have much luck with a Qutest , 384 was the limit from an Ultrarendu before I got similar noise artifacts.
Even though the qutest is supposed to be good for 768.

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On HQPLAYER, what filters are you using?

Are you using HQP embedded or Desktop?

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Yes, and the clicks get worse when I play my digital files at 45RPM

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Interesting, thanks. I tried 192 for a few hours today and didn’t hear any clicks but I was working at the same time so I can’t be definite. I went up to 384 and I did hear a few clicks. Worth experimenting more with I think.

However I do want to go to max res of 705/768 because that’s when the first stage of upscaling inside the dac is switched off - I think it does make things sound better.

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All sorts of filters - the clicks are common to all I have tried. HQP embedded.

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Please advise the spec’s on the computer you are using for the HQplayer embedded.
Thanks

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I did some more tests and found the following:

  • Clicks and pops occur on USB input of Qutest at all levels of upsampling I tried (most of them) using HQP. No clicks and pops heard via SPDIF.

  • This one is the big discovery: Clicks and pops DO NOT occur on USB input of Qutest at the max level of upsampling (768khz) using Roon native upsampling.

  • Using HQP and upsampling to 768khz into USB input of Qutest I quickly get white noise in 1 speaker.

  • I have played 768khz upsampled material via Roon upsampling all day into the USB input of the Qutest and had no problems - no white noise, no clicks or pops

  • I wondered on my roon core / HQP machine (Intel j4205 wtih 8GB ram) was overloaded so I looked at top to find the CPU usage:

    • in HQP Clicks were happening a lot on HQP with poly-sinc-long-lp. Upsampling to 705khz - here CPU load was 42%. This is 42% of 1 core and the CPU has 4 cores. Load varies with other filters (higher and lower than this) but clicks and pops occur sooner or later in all the ones I remember trying.

    • Roon upsampling to 768khz does not cause clicks. CPU load = 29-30%

  • HQP takes 5GIB (~60%) of memory. Roon takes 15%

  • All tests above were PCM - PCM

I think this is now a question for HQP forum so I am moving the question over there. Thanks for the replies so far. I am glad there is not a hardware problem and it is interesting to see the difference software can make!

1 Like
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Hello
I have the same problem with my Chord Qutest since the Apple Ventura upgrade. But I have the problems with the native Roon upsampling. Today, after a 14 day holiday, I had the clics and pops even without upsampling. With my second DAC Audioquest Dragonfly Cobalt I have no problems. When I use Audirvana(the old 3.5 version)I even have no problems with the Chord Qutest. It is very silly and I an confused.
At this moment everything works correctly using no upsampling and only lossless data after sending everything back to standart.
Regards RĂĽdiger