Does the DS not play DFF files?

I’m able to stream and play DSF files with my DS, but DFF files are not playing. Using MConnect and streaming from my Synology NAS using its Media Server. It’s not an issue with the NAS Media Server because I am able to stream the same DFF files to my OPPO and they play fine.

No real answer here, just some background:

The question is where is the file being unpacked into a stream of bits. For the DS/Bridge someone has to be repackaging the data into DoP and sending it to the bridge - any such repackaging will hide the source format of the file - i.e. the DS/Bridge doesn’t know whether it’s a DFF, DSF, iso, (or packed DoP in a wav…) Unlike the bridge, the Oppo can decode .dff, etc. internally it doesn’t need DoP’ifying so if, for argument sake, the streamer only DoP’ifys DSF files that would explain the difference.

Another possibility is that perhaps the Bridge understands DSF files (or even DFF files) but I’m sure it doesn’t decode any such files that are DTS encoded (SACD’s DSD lossless compression format) since that takes serious software power or custom hardware. If that were the case it’s not DSF vs DFF, it’s whether the source is DST’ed. (Less common on stereo files, but they do exist.)

Looking at the DS screen, it is reading the DSF file as DoP. Synology Media Server must be repacking as DoP and sending to DS just as you thought. For whatever reason, it is not doing the same for DFF. Time to investigate further.