If it's intercepting the signal and reprocessing, I'd like to know what it is actually doing, is all.
Well not going to beat a dead horse here, since apparently no one knows what is actually happening or what sort of circuit is involved.
Pretty straightforward question.
Kind of telling when you get defensiveness in answer, right?
The sample rate clock running the DA converter you are listening to being stable and jitter free leads to the best DA performance. Kind of obvious... unstable jittery clock ticks would smear the audio time-wise. Back in the days when some early digital converters had less than optimal clocks, an upgraded sample rate clock led to better DA playback performance.
Digital audio shuttled between devices is a moot point. As long as all the ones and zeros get there... mission accomplished! It's the DA converter we're listening to the audio from and that's the clock that needs to be jitter free. The in-between device data shuffle can jitter around, pause and lag as it pleases as long as the data gets from point A to B in time.
So when someone comes along talking about DA converter clock jitter but tries to superimpose that discussion on data transmission between devices with HDMI with no connection to the DA sample rate clock in any way... well, there will be questions!
When the answer is defensiveness and changing the subject... there ya go! Listeners being subjective is nothing new. I've heard people listening to dropout riddled digital audio systems and appearing oblivious to anything wrong. Not jittery. Not occasional error correction warbles. Straight up mutilated audio clicking and popping away with abandon. Forgive me for not taking such a person's critique seriously, right?
We're all listening if someone has discovered a cheapness element in some products that has a slick cure! Or whatever the premise might be. I can just buy that cheaper one and then one of those thing? Ya, I'm listening!! So far only defensiveness or changing the subject in answer to any questions.
People like the sport of busting someone on the internet. Someone would have recorded the output before/after this thing and posted spectrogram plots if there was anything to show.