MQA dropouts - a summary

Rooners (and listeners on other platforms) are reporting annoying dropouts when streaming MQA files from Tidal. I’ve experienced this myself. I’ve done some “research” on this and here are my observations:

  1. There are NO dropout issues with CD-quality flac files (16-bit, 44.1KHz or 48KHz) from any source (Tidal or Qobuz).
  2. There are NO dropout issues with Hi-Res files of any sampling rate from Qobuz (up to and including 192KHz). Big win for Qobuz!!
  3. Tidal/MQA dropouts are NOT a problem if you’re using a combined streamer/dac (e.g., the Bluesound Node streamers).
  4. Dropouts ARE a problem when using separate streamers and dacs—specifically connected via USB. I’m using a Pro-Ject Stream Box S2 Ultra connected via USB to an SMSL-SU-8S DAC.
  5. Dropouts do not appear to occur when you connect your separate streamer and DAC via either a coax cable or toslink. BUT, it’s my observation that the way DACs work right now, you are unable to do the final decoding of MQA files (to 192KHz) when using coax or toslink. That final unfolding requires a USB connection. In any event, the only output my Pro-Ject streamer has is a USB output.
  6. Interestingly enough, when using streamer/DAC separates connected via USB, lower sample rate MQA files (44.1 and 48KHz) do NOT throw dropouts.
  7. But the higher sampling rate MQA files on Tidal (96KHz and 192KHZ and beyond) do manifest occasional or even frequent and very annoying dropouts.
    I must confess, this business flummoxes me. Presumably the streamer is delivering a bit-perfect stream to a DAC capable of fully unfolding the MQA file. Why higher resolution MQA files hiccup like this while streaming is a mystery to me.
    I’ve tried all sorts of settings in Roon to no avail. One tweak I made in Roon is to always prefer Qobuz files when using the Pro-Ject streamer. I could cap the sampling rate that Roon processes to 48KHz but that would also cap the Qobuz files that are not problematic. One suggestion to the Roon staff: program a switch that allows us to specifically cap the sampling rate on MQA files.
    FWIW, I’ll stick with Tidal because they have lots of music unavailable on Qobuz. I’ll have to live with the annoying dropouts for now and hope that a firmware update on some piece of equipment at some future time fixes this issue. That, or I’ll be buying a combined streamer/DAC.
    Does anyone have further observations or corrections about any of this.

Nothing useful to add except I haven’t seen any issues streaming MQA and I’m not aware of any reports that things appear to be amiss. However I always do first unfold in Roon.

I have similar, but not exactly the same experienced as Bob describes.

My setup is Roon Core (NUC) - Bluesound Node (130) - Cambridge DacMagic 200. Roon is configured with TIDAL and Qobuz services and also connected to my own music library (FLAC files on my Synology NAS).

First of all: I do not experience any problems with playback of non-MQA material (Qobuz or my own FLAC-files on the NAS). The exeption I think, is quite infrequent problems when such material is mixed into a playlist which also contains MQA material.

When connecting using USB, the DAC is unable to process MQA. Continuous dropouts, typically once a second or so, and the MQA indicator light on the DAC switching between MQA decoding and no MQA. So it really does not work. I have seen some kind of statement, do not remember if it was from Cambridge or Blusesound support, but this problem was acknowledged and the recommendation was to either use spdif or disable MQA capabilities for the external DAC in Bluesound setup.

When connecting using optical or coax, far better, but occasional problems with dropouts and even sometimes inability to switch between MQA and non-MQA (i.e. playlist with mixed source material) sometimes (not often, though) resulting in no playback (silence). I have not been able to spot any differences between optical and coax.

In previous versions of Bluesound SW (BluOS), I did experience similar problems with USB connection with the DacMagic 200 when not using Roon, but that was resolved through a Bluesound SW update. And I have currently no problems when streaming using the Bluesound app or when streaming from TIDAL (TIDAL Connect). So it appears to somehow be a Roon-related problem, even if the root cause, for all I know, could be in the Bluesound Node or the DacMagic 200.

I have not been as systematic in testing as Bob, but anyway I really would like the problem to be resolved. I am currently on a Roon trial subscription, so the volume of testing is also limited. Although I am very happy with Roon functionality in general, these problems make me uncertain about whether to sign up for Roon or not. So I really hope this could be fixed somehow.

I’m having exactly same problems using macOS Roon connected to a iFi xDSD Gryphon via USB.

Roon for Windows via USB doesn’t suffer the problem.

If you’re referring to streamer output to coax / toslink, first unfold / MQA Core decoding is certainly possible in certified MQA transports like our streamers. This depends on the streamer design, and whether they are MQA certified.

If you’re referring to MQA DAC decoding MQA signal from coax / toslink, that’s possible from some DAC such as Esoteric K-01XD players or others in the same series. This depends on the hardware architecture of the MQA DAC.

Try direct Roon Core USB output to your DAC, bypassing anything else in between. If this works, you know which component is causing you problems.

I surely do wish I had discovered this thread BEFORE I purchased my shiny new SMSL-SU 10. I didn’t really buy it for MQA but I thought – why not try it?

It just cuts off the first 1/2 to 1 second of the start of any MQA track. Gapless playback works OK on MQA if the source material is truly gapless, so that’s good.

No issues of any kind if I just don’t do MQA at all, which obviously will be the plan if I can’t get this sorted.

The DAC claims to support full MQA over SPDIF so I’ll be trying that next. Right now I’m running it via USB to my Mac Mini Roon Core.

Not a tragedy or anything but once (or if) this is fixed, I’ll be grateful. It’s a bit of a buzzkill on what, otherwise, seems to be a magnificent product.

Doug, I just have to laugh out loud, because I (the guy who started this thread) just purchased the very same SMSL SU-10 (before I saw your post). I was hoping that it’s very different components would, maybe, fix the MQA problem. As I write, my shiny new DAC is in transit from China. Oh well, at least I won’t be horribly disappointed when the dropouts start during MQA playback.

There are other benefits to the new SU-10 DAC. A big one for me is the ability to establish a bluetooth connection to the DAC using the LDAC codec. That opens the possibility of streaming other services from my phone into my system–notably SiriusXM. The reviews I’ve seen also emphasize the quality of the build of this DAC. It sounds like the product is first-rate for a sub$1K DAC. I will also take the view that at some point I can use either coax or toslink to also fully unfold MQA. Right now, I’m stuck with USB because that’s the only output I have from my Pro-Ject Stream Box.

I’ve been turning to MQA a whole lot less lately. I have subscriptions to both Qobuz and Tidal. My Roon instance is set to default to Qobuz whenever possible. I’ve also set MQA to NOT be preferred over anythng else. Finally, even though I’m currently paying for the Master quality service, from Tidal, I’ve set Tidal streaming in Roon to HiFi. So in most instances, I only see the standard CD quality streams via Tidal. I note with interest that 44.1 and 48 KHz MQA streams do not hiccup at all and they are streamed as part of the HiFi level service. I do NOT see 96 and 192 KHz MQA streams. I do see 88KHz MQA streams and these dropout once in awhile. Oh well, it’s irritating but not a deal breaker.

If I have any breakthroughs in the use of my new DAC, I’ll report back.

1 Like

Aw man. Well it IS a great product so you should be pretty happy with it, save for this

Just for shiggles I’m going to try it with TIDAL on Mac via USB and bypass Roon just to see if the issue persists. My expectation is that it won’t, but even if it doesn’t, dropping out of the Roon experience isn’t on the table for me. I’d rather give up smooth MQA than Roon.

Best of luck! I’ll post here how I get along once I find one of my coax cables to test SPDIF / MQA / Roon

I should add that I don’t seem to have issues with this SMSL SU-10 DAC using Roon + Tidal + MQA when the sample rate is 96khz or less. 192khz files are the ones that cause trouble.

1 Like

This is great summary.
And I’m just dropping the following thread as a reference because I think it’s connected.

1 Like

Thanks - very interesting.

Sounds like my challenges are not as significant. The only issue I’m having is the SMSL SU-10 DAC (or Roon, or both) are just cutting off the first half second or so of 192K MQA unfolds. Annoying but minor. Not experiencing cutouts, static or anything else like that.

I’ll move on from MQA entirely after a little bit more fussing with it. I’d like to have the option but I’ll live if I don’t get it.

I seem to have sort of solved this issue that I was having. It’s more of a workaround than a real solution, but…for me…preliminarily…it worked.

  1. Turn off volume leveling in Roon for this Zone. The DSP I tried (EQ) seems to be OK but Volume Leveling seems to mess this up.

  2. Use an actual Apple USB-C cable and connect to the USB-C port from the SMSL SU-10 to the Thunderbolt port on the Mac Mini. A different or generic USB-C cable might work, and seems like it should but I haven’t tested it because this is what I had on hand. And, it seems like an Apple move to have anything other than their own cable work perfectly. I say this as a loyal Apple fan.

  3. Profit.

In my experience, using any other port on the DAC or the Mac Mini, no matter the cable, caused the issues I’ve described.

So - using a 2021 Mac Mini as Core, running Roon Server 2.0 build 1182 connected via USB-C to the new SMSL SU-10 DAC, streaming Tidal from Roon, with volume leveling OFF, appears to cause no stammering or cutoffs with any MQA file I tried to stream.

It’s the only thing I’ve found that works, so far. If issues arise I’d try bypassing any DSP at all. Not sure MQA is worth that.

Of course, one could just not bother with MQA, which I would find understandable.

ADDED: I also found that running Coaxial from Bluesound Node 2i direct to SMSL SU-10 yielded good results.

I think I’m done with this!

1 Like

My new SMSL SU-10 DAC arrived today. There’s a lot to like about this DAC and I’m very happy with it, BUT, I still have dropouts with MQA files with a sampling rate of 96khz and above. I have these dropouts using a USB connection between the streamer and the DAC. At some point, I’ll be able to test a coax connection to see if this improves matters.

I will have to reevaluate my interest in streaming HiRes MQA files. I may decide to cut back to the HiFi level service and save money on the Master quality streaming. I do intend to stick with Tidal, but I’m about done trying to get MQA to work properly. It shouldn’t be this hard.

1 Like

In the interest of being thorough, I tested this situation with a basic WIndows Core i3 laptop I have, connecting it direct to the SMSL SU-10 DAC via USB. I wanted to rule out MacOS as a culprit.

Indeed, the behavior is the same with Windows 10. It cuts off the first half second of any MQA track above 96khz if Volume Leveling or DSP is on.

So, switching cores did not prove fruitful for me.

I guess it comes down to how committed one is to MQA and using this particular DAC.

Best solution for me so far is M1 Mac Mini using Apple USB-C cable direct between T-bolt port on computer and USB-C port on DAC. Even then, if I skip a track, it might cut off the first half second if it is the aforementioned file format. Just letting things play generally is smooth.

1 Like

Thanks for the update. Here’s mine: I grabbed my Node Gen3 streamer (which I’d been using for a system elsewhere in my house). I connected the Node to the SMSL SU-10 DAC with a digital coaxial cable. I’ve found that 96khz tracks play just fine with this arrangement (they were skipping frequently when I used the USB connection). 192khz files skip but only a little. Definitely a lot fewer dropouts with coax vs usb connections. Since there are only a few 192khz MQA files being served from Tidal, the skips are a very tiny nuisance. I may be motivated to try this with an optical cable, but that will be for another time.

Doug is right: are you committed to playing MQA files? Honestly, I get great results with Qobuz high res files. So I may step down from the master level service with Tidal to the high-fidelity level service. I’ll think on it.

1 Like

This is the exact same experience I had with my Node 2i.

I can’t seem to quit this topic.

My curiosity is piqued so I downloaded the Tidal app to my Mac and connected the SMSL SU-10 directly to the computer, bypassing Roon entirely.

The 1/2 second cutoffs are still there. Exactly the same.

So, in this case, it’s the DAC, or the XMOS chip within the DAC. I do not know.

However, using a Bluesound Node 2i and it’s built-in (IMO less ideal) DAC works just fine with 192k unfolds in terms of cutoffs, skips, etc.

But I don’t think the fault lies with Roon. Or Windows. Or MacOS. Or TIDAL.

This now ends my experimentation with this! I hope anyone else struggling with this knows…you’re not alone!

Here’s one additional observation: if you use the Bluesound Node as a streamer, connected to an external DAC, and use the BlueOS app, you do not get the skips. If you’re using the Node 2i, you can connect to the SMSL DAC via either coax or toslink optical and should be able to fully unfold MQA files, I’m not sure if this will fix the 1/2 second cutoffs. But try to BluOS app and see what happens.

And yes, I moved to external DACs because I found the Node’s on-board DAC to be substandard, too.

Good luck.

1 Like

Just a thought:
Most of the problems I have heard about with Roon, Bluesound, external DACs and glitches seem to be with DACs with ESS chips (like my Dacmagic 200 Bob’s SMSL SU-10) and I have also seen reports where these DACs, that have a jitter reconstructing filter, have trouble with handling bit streams with a lot of jitter (see for example Topping D90SE Review (Balanced DAC) | Page 91 | Audio Science Review (ASR) Forum; post #1,808).

Could it be that Bluesound’s handling of hi-res MQA material over RAAT causes a lot of jitter? Which sometimes causes the ESS-chip to stop the conversion which again results in the glitch we hear? And that the max jitter that the DAC accepts is related the sampling rate?

Possible but trying a Topping E50 DAC connected directly to the core over USB didn’t have this issue. I think it has a ESS chip.

Unfortunately, the E50 will only unfold MQA when fed USB, so it’s not apparently possible to send MQA signaling over Coax to it from a streamer.

I got tired of multiple boxes connected together to try to accomplish what one box should do on it’s own, so for the meantime I’ve given up on MQA. Just a personal preference.