Bitrate/bitdepth changes lose audio

[Calico]

PROBLEM: When going from one song to the next, with a change of bit depth and/or rate, frequently my DAC loses its lock, and either stops playing starts making clicking noises.

SETUP: Moode 9.2 on RPi 4, using integrated Qobuz client as the source, outputting SPDIF via an Allo Digione to a Theta Generation VIII series 3 DAC.

DIAGNOSIS:
1. The DAC is capable of everything from 16/44 to 24/192. Playing individual songs at those bit rates/depths works normally, so we can pretty much rule out that the DAC is the problem.

2. The problem arises when going between mismatched songs in Moode.  For example, a playlist with Song A at 24/48 and Song B at 24/192.  When Song B begins, the DAC very often (not always) loses lock.  A reboot solves this.

QUESTION:
Theta says this error would happen if the source (Moode) drops the PCM flag.  Is that perhaps the cause?  Or is there another cause which should be investigated?

Thank you.

[Tim Curtis]

The symptom "When going from one song to the next, with a change of bit depth and/or rate, frequently my DAC loses its lock, and either stops playing starts making clicking noises." suggests an issue with the rate lock mechanism in the DAC.

IIRC there was one other DAC years back that a rate lock issue but it had to do with some sort of mechanical relay that was involved in signal detection and rate locking. 

If the DAC has a USB input you could try it and see if the issue occurs.

[Calico]

No USB input, unfortunately.

I don't think your explanation captures it, because in my example, the DAC locks and plays both Songs A and B just fine if I start them from cold on Moode. In other words, absolute compatibility with the bit rate and depth is definitely there.

Rather, the problem is that there is something in the output from Moode and the Digione BETWEEN SONGS that breaks the DAC's lock. So Song A plays, but then the lock is lost just as Song B starts (assuming they're on a playlist).

What do Moode's unusual DSD settings do? Could they be tricking the DAC into thinking it's not getting PCM for a brief moment between songs?

[Tim Curtis]

I'm not sure what you mean by "Moode's unusual DSD settings".

So lets assume that there is this bug "there is something in the output from Moode and the Digione BETWEEN SONGS that breaks the DAC's lock" then I would expect other users that have a Digione would experience the same sample rate lock issues with their DAC.

If other users report rate lock issues with Allo Digione and their DAC then I'll investigate.

[dwlacroix]

I have the same problem on a Klipsch PowerGate (USB connection). Solved by enabling the SoX Resampling

[Nutul]

I have the same problem on a Klipsch PowerGate (USB connection). Solved by enabling the SoX Resampling

Of course... nice trick; as this will resample everything to one and only bitdepth-samplerate, so that no change will happen to the stream, and the DAC will be happy...

To me, the problem may lie in the fact that playing the songs individually, MPD is stopping/re-starting the stream; while when on a playlist, some re-initialization from scratch of the stream does not take place, and some (all?) SPDIF interfaces may not be (indeed are not?) happy with it...

Isn't there a setting in moOde (sorry, not at home ATM...) related to playing silence between tracks, or something in the line?
Also, the OP addresses DSD settings - maybe he means DoP? as, AFAIK, SPDIF does not have the bandwidth to play any native DSD samplerate...
Maybe he indeed plays DSD over PCM, and MPD between DSD tracks does (or does not do) some set-up with which the SPDIF is not perfectly happy?
Just mumbling...