D/A converter in TI Aureus DA710?


The last time I used my hk avr7550hd the fan started making unnatural noises. I wanted to set it up as a pre pro for my hk990 because its D/A converter is 34 bt and the 990's is a pair of AD1955 24bt/192kh chips. So before I sent back the avr7550, I thought, fry then, and set it up as pre pro. It squeeled for a minute and then settled down so I could compare SQ eventually after it warmed up.

SQ is much better using avr7550hd's converter and of course with Dolby Volume which I love.

I can't find info on this TI Aureus DA710 even though it is commonly used in avr's. I wonder if someone can explain this 34 bt chip. Is it NOS or asyncronous? Does it oversample or upsample?
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