I'll again add this is just a symptom of the design of the DAC board. It's not the actual ESS 90382 DA converter chip, there's more to a DAC unit/board than the DA converter chip. I have a Topping D50s which has dual ESS 90382QM DA converters and there's no jitter noises when rates change either via USB or via the optical & coax inputs.
It'll happen periodically because when you play a playlist of digital audio files at one rate (16bit 44KHz PCM for example) then the DAC's clock is synced at the beginning and is locked to that rate throughout that playback session, if the source then changes to a different rate then the clock is resynced to operate at the new rate, this is when you're hearing this reclock, the audible jitter you're hearing is the period where the DAC is operating out-of-sync with the source. Many modern DACs automatically silence such jitter noise when the clock is not locked, for those DACs that do not silence such noise there are SPDIF reclocker devices that can help.
As I touched upon in an earlier comment USB is different to SPDIF interfaces as USB is a asynchonous (two-way) data communication interface which is managed by a device driver on the source and dedicated chip on the DAC, the source knows what the DAC is capable of and negotiation occures between the source's driver and the DAC.
SPDIF is one way communication standard, e.g. the source sends a signal out of it's SPDIF interface, whatever is connected at the other end of that interface is unknown, the receiver just deals with what it receives.
If these boards of yours work OK with USB I'd suggest using USB.
It'll happen periodically because when you play a playlist of digital audio files at one rate (16bit 44KHz PCM for example) then the DAC's clock is synced at the beginning and is locked to that rate throughout that playback session, if the source then changes to a different rate then the clock is resynced to operate at the new rate, this is when you're hearing this reclock, the audible jitter you're hearing is the period where the DAC is operating out-of-sync with the source. Many modern DACs automatically silence such jitter noise when the clock is not locked, for those DACs that do not silence such noise there are SPDIF reclocker devices that can help.
As I touched upon in an earlier comment USB is different to SPDIF interfaces as USB is a asynchonous (two-way) data communication interface which is managed by a device driver on the source and dedicated chip on the DAC, the source knows what the DAC is capable of and negotiation occures between the source's driver and the DAC.
SPDIF is one way communication standard, e.g. the source sends a signal out of it's SPDIF interface, whatever is connected at the other end of that interface is unknown, the receiver just deals with what it receives.
If these boards of yours work OK with USB I'd suggest using USB.
