I was contacted by James at dCS, and he asked what the display showed when this ocurs, and it appears to implicate the DoP detection mechanism and/or the switch between PCM and DSD modes.
I sent him this:
The easiest way to see this is to use software like JRiver to play the file over USB and that has a setting for how much silence to insert before sending music data (Tools > Options > Audio > Settings > Play silence at startup for hardware sync > (amount))
When stopped, the display reads 0/176.4.
When it detects the DSD data, it switches to read DSD.If there is no delay, the music does not start until the display switches to DSD.
If there is silence inserted, it switches to DSD, then playback may start properly.These operations all involve pressing “stop” and then “play”:
If I select no silence, music starts at what is approximately 0.84 second into the track (determined by looking at the track in a music editor.)
If I select 1/4 second silence, music starts about 0.25 second into the track.
If I select 1/2 second silence, music starts as it should at the start of the track.What is notable is if I jump back to the beginning of the track via USB, it will continue to play the beginning of the track properly once it “knows” it is DSD (which is why you have to hit “stop” to get it to read 0/176.4.)
Via Network, the display changes to 24/176.4 and then to DSD even if I jump back to the start of the track, so there is no way to play the track from the beginning as, once again, the delay seems to be in detecting it is DoP DSD rather than PCM.
The issue seems to be that once the unit knows a datastream is DSD, it doesn’t send the data frames it has received to that point to the DSD decoder, it apparently just discards them and interprets all FUTURE received data as DSD until the end of the track.
Changing the buffer setting does NOT affect the loss of the first part of the DSD track, it is lost whether the buffer is on or off.
The behavior I mentioned above with the unit defaulting back to PCM is clear between inputs:
- The USB input keeps the data type as DSD, so you only lose the start of the first track you play in an album or playlist as long as you let the songs play through and don’t jump to a new track. Jumping to a different track causes the player to do DoP detection again and again the start of the song is cut off.
- The Network/DLNA input resets to PCM with the end of each track, so you lose the beginning of each successive track.
So as I mentioned, say you have two DSD tracks that play as an album:
Via USB:
Played continuously starting at Track 1:
Track 1: First part cut off
Track 2: Plays normallyJump to Track 2:
First part cut offJump back to the start of Track 2:
Plays normallyVia Network:
Played continuously starting at Track 1:
Track 1: First part cut off
Track 2: First part cut offJump to Track 2:
First part cut offJump back to the start of Track 2:
First part cut offThis behavior means it is impossible to properly play a DSD album via the Network, and the only way to properly play a DSD album via the USB input is to start playback and jump back to the start of the first track - neither is a really good option.