Li Bo: I'm not sure how changing the sample rate for SPDIF would have an effect of the SNR if you are only passing digital signals. I have had excellent measured results with the Via chipsets at all sample rates up to 192 KHz at 24 bits on the digital output. Perhaps you can explain how you measured the performance and that may explain your results. Normally if all of the data of the original file is present then any limit on SNR is a function of the DAC. If the data is not the same as the original file then there are more serious issues to be resolved, and it probably would not be useable with Dolby Digital or DTS.
Higher sample rates for digital content and digital interfaces are becoming more common and I think it would be a serious mistake to limit the performance of the platform.
Hi, Takashi
According to our HW test, S/PDIF at 48K sample rate has best SNR, so this
limit can make >S/PDIF work better.
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