To make ASIO support happen the Mytek ASIO driver has to be redeveloped to include DSD bitstreaming capabilities (looks like this would be Firewire initially). Mytek are dragging their feet with this. However what does work with the Mytek Firewire/DICE driver is the dCs byte packing scheme (specification here:
http://www.computeraudiophile.com/files/DSD%20over%20USB.pdf). This is sending a packed version of DSD (176/16) with an 8bit padding identifying the stream as actually DSD. The Mytek firmware 1.20 knows how to decode this stream in its FPGA. One other Windows application can reliably send this DCs packed scheme but its not a patch on JRiver's feature set. Pending Mytek getting its act together those of us who are JRiver owners are currently unable to play native DSD. One solution would be to have a dCs option in JRiver MC which is very similar to the packing scheme for the Playback Designs DAC.
"As you can see, the top 8 bits of each sample are 0xAA. This represents a negative DC offset, which won't be seen in real‐life audio, so we can use it as an indicator for the DAC that the data it is receiving is DSD rather than 24/176.4 PCM. Additionally, it means that if we try and play the DSD stream via a DAC that doesn't support it, the output is noise, but it is 48dB down ‐ the user can tell they are playing back an unsupported format, but not in a speaker‐destroying way. For PC‐audio based solutions, if the playback software is DSD‐aware, it can output 0xAAAAAA samples by default
to represent a safe DSD mute." (Playback of DSD Audio over USB – A Suggested Open Standard)
As it stands now JRiver is potentially losing prospective (not current!) customers to the functionally inferior competition by users who have DSD and a Mytek DSD Dac and no way to convey it across the wire using JRiver. I have plenty of DSD files and a Mytek DAC and am willing to test any attempt on JRiver's part to implement the dCS scheme. I will also lobby Mytek to send a loan Mytek DAC to JRiver for testing.
A second desirable feature would be the ability to write Id3v2 tags to the Sony *.DSF file used to store uncompressed DSD. This specification is also well defined (
http://www.dsd-format.sony.net/en/index.php) and not proprietary.