Roon Nucleus + won't play DSF files

Yesterday, the dealer was able to successfully install Roon Nucleus + in my system. The nucleus is connected to my Classe SSP-800 processor via HDMI and is able to properly play any of my FLAC files including multi-channel files. However, when I tried to play a DSF file, I no sound was emitted but it was obvious that something was “playing” given that the waveform was displaying properly. Indeed, the first time this happened, I had to re-initialize the SSP-800 to get it going again.

I still can use my OPPO UDP-205 as an endpoint but unfortunately it can only play back 2-channel DSF files due to a design shortcoming of the Mediatek chip that the OPPO uses. One of the reasons that I bought the
Nucleus + was to play multichannel files. The Nucleus + will only play FLAC files (both multi-channel and stereo files at present. Incidentally, the OPPO is connected to my SSP-800 via HDMI (for video) and one pair of XLR connectors for audio.

Nothing in the Roon Settings jumps out at me but then I am quite new to this. It seems that it should be something simple in the Settings but so far I can’t find it.

Hopefully someone has some suggestions.


According to Classe’s FAQ the SSP-800 doesn’t support DSD at all:

Go into your Roon settings for that audio device and set “DSD Playback Strategy” to “Convert to PCM”. The Roon core will then convert your DSD streams to the appropriate bitrate of PCM and then it should work.

I am trying to post this again.

"Thank you for the quick response.

The default is “Convert to PCM” for this device and unfortunately that is not working. Indeed, when I tried switching from Roon to watching my satellite TV,
I could not even get sound for that and have had to (successfully) re-initialize the SSP-800.

Incidentally, just to be clear, I would be quite happy for DSF files to be converted to PCM for the reasons outlined in the SSP-800 FAQ.
Playing DSF files natively is of little importance to me.


Moved to @support.

Cheers, Greg

Hello @Jim_Ridgway,

In the “Device Setup” screen for your HDMI output zone, could you try setting the maximum sample rate to “96 kHz”?


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Thank you for the very fast reply.

Eureka, it works! Setting “Max Sample Rate (PCM)” to “Up to 96kHz” in the Device Setup for my HDMI output zone (in my case it is named SSP) did the trick.

However, a couple of things to note:

 1. In my situation, I had to swap the rear and side channels in my 7.1 layout to get the intended soundfield.  However, using the rear channels instead of the side channels is an interesting option that I may have to experiment with.

 2. To get post-processing on 2-channel material, "Send Stereo/mono content as 7.1 MUST be turned off.

 3. I cannot get post-processing on 2-channel material (i.e. 2-channels synthesized to 7.x) but not multi-channel.  An example would be Tubular Bells which is DSF 4.0.  Only the FL, FR, SL, SR (originally RL, RR before I "swapped" the Rear and Surround channels) will play.  The Mode comes up as Discrete on the Classe SSP-800 and cannot be changed.  I am fairly sure this is a problem/short-coming with the Classe.

 4. I noticed that the video output from the Nucleus + is 480p according to the Classe information screen.  What happens as a result, is that the screen is a bit distorted as is the Classe On-Screen Display (OSD).  It is certainly quite functional but it is a niggle and if you are like me, you don't like niggles.  Of more concern is that it is outputting 480P.  I say this because somewhere in my OPPO Manual it says that 720P or 1080I is required to guarantee proper higher resolution audio transmission.  Perhaps this is a non-issue but you never know.

In summary, the relevant settings for this to work are:

DSD Playback Strategy = Convert to PCM

Max Sample Rate (PCM) = Up to 96kHz

Max Bits Per Sample (PCM) = 24 (this probably doesn’t matter in my case but I have no 32 bit files anyway)

Channel Layout = 7.1

Send stereo/mono content as 7.1 = No (to ensure post-processing of 2-channel material. The settings as it
appears now is a bit counter-intuitive, at least to me)

Thank you so much for your help. This is now turning into a terrific Labour Day long weekend here in Canada.

Jim Ridgway