I'm still alive, and need some research help

I'm (slowly) working on my next video, in which I do a bit of mythbusting -- do portable CD players with an anti-skip memory buffer actually reduce audio quality? It's something I said in my "portable CD players buyer's guide" video from a few years ago, but was recently called out on as supposedly being not true. So now I need to find out for myself.

Here's where I could use some help: Sony's Discman players at least used a dedicated "memory controller" chip that sat between the DSP and the RAM. I suspect this chip is what's responsible for any audio compression that takes place. I found the service manual for Sony's first Discman with ESP, the D-515, and it lists this chip as being part number CXD2511R. Problem is, that appears to be a custom chip Sony developed.

What I could use help on is trying to find more detailed info about this chip. While I haven't been able to find one, I suspect there's a datasheet out there somewhere about it because I was able to find a reference that it was also used in a Pioneer car stereo (which means Sony at least sold it to other manufacturers, if not on the open market). I'm hoping that datasheet -- or just any technical information, really -- could shed light on how the chip works and what kind of audio compression it implements. (A mini-spoiler: While I'd love it to be ATRAC as that would really tie things together nicely in the narrative, my guess is it's actually ADPCM.)

Anyone up for the challenge?

Otherwise, thank you for your patience and support as I'm on a semi-hiatus. I'm hoping to get back into the groove of video production again, though perhaps with a more ad-hoc release schedule (don't worry, you'll always get to watch them in advance). My new day job is in some ways very similar to my old one, but it's also very different in others, and I have a lot of work ahead of me -- which has largely been occupying my mind these days. This Discman video has enough of a gravitational pull to distract me, though, which is a good thing. I just want to make sure it's as good as it can be.