Audiolab M-Dac +

Hi! I tried to no avail with DSD playback. The Audiolab M-Dac+ is connected to a macbook air via USB with roon bridge installed. Roon core (trial version) is installed on a iMac over a local area network. I tried various device settings on roon but all i get is high resolution PCM playback and not DSD.

A peculiar thing is that the sound output will always switch back to “built-in” output even though audiolab m-dac + was initially set whenever i play any DSD title. Why is that so?

Hi @Tang_Carol ---- Thank you for the report. May I kindly ask you to please provide a screenshots of the audio settings you are using in Roon.


Hi! Eric,

I tried tweaking different permutations of settings but to no avail.

setup as requested:

Roon Bridge: MacBook Air (latest Sierra OS 10.12.3), Audiolab MDAC plus (latest firmware 0.020) connected via USB to roon bridge.

Roon Core: iMac (latest Sierra OS 10.12.3), DSD music stored (mixture of ISO & DSF files format) via USB connected to roon core, other PCM titles stored on Synology NAS.

Wireless Network connects roon core/bridge.

Audirvana installed on Macbook Air has no problems with DSD playback…

I see there is a user with the same DAC and posted a request for him to share his settings…though i am not sure whether the mdac+ is connected via roon bridge or core. I tried emulating his settings to no avail too.

Hi @Tang_Carol ----- Thank you for providing us with the details of your setup, this information is very useful when evaluating these types of issues. Can you please also provide the details of your network configuration / topology? I would like to have a clear understanding of what networking hardware you are implementing to make these connections possible between your device.

Furthermore, in your troubleshooting of this issue, at any point did you try connecting the DAC directly to your iMac which is hosting your Roon core? If so, was the experience the same?



spent to much time troubleshooting whereas i should be enjoying music…maybe for the record, Audiolab Mdac + is not a good fit with Roon 1.3 bridge + Mac Sierra OS for anyone who is contemplating such combination.

Meanwhile, i just lean back on the non-high res but reliable and user-intuitive sonos.

Hi @Tang_Carol ---- Thank you for the follow up. I met with my team and one of our developers today to discuss this behavior you are currently experiencing while working with the M-DAC+.

Can you please provide us with a screenshot of your “zone settings” (this can be found by clicking on the zone icon at the bottom of the application window) and a screenshot of your DSP settings if they are being used.



for those Mdac plus owners, the solution is either to disabled DSP engine or enable DSD sample conversion.

But DSD256 still remains a mystery even though mdac plus supports DSD256 natively and software such as audirvana has no problems in playing DSD256 titles.

Correct me if i am wrong that Roon 1.3 or future version will not support SACD ISO formats in DSD playback?

Thanks for letting us know @Tang_Carol – we discussed this today and we’re going to investigate a bit further. You’re sure Audirvana is playing DSD256 without any conversion, right?

I won’t say never but it’s not something we’re planning to do in the near term, since there’s a lot of work involved.

for the record, the solution is either to disabled the DSP engine which i prefer or ensure the “DSD” is choose under the “Sample Rate Conversion”…Many thanks Eric for your patience for helping me to resolve this issue. Only thing left is DSD256 playback.