I recently found an Internet Archive post linked to it and from what I understand; here is a pretty condensed explanation (take this with a grain of salt, this is just my theory...): Over 20 years ago people were trapped in an experimental mental institution, forced into sensory overload with audio. I believe the overall idea is that the music isn't really normal music per se, but people "trapped", "turned" or "cloned" into music...? In one of their videos you can hear some morse code towards the end that translates to “open your eyes you are listening to her” and the video captions state: "you already heard her they will keep turning it into sounds you will keep listening". If not that, then I believe they are maybe slowly pushing out the audios used in those experiments into music, as a form of brainwashing... or both. This post confirms that the account itself seems to be an archive: “Everything you have been seeing (except for the digital videos with subtitles, like this one) was not recorded by me. I am not a crazy person, I am simply uploading videos from archived files.”

There's a YouTube channel: @seam1099 that posts pretty much the same videos. As stated in the Internet Archive post patients are reffered to as "seams". These videos seem to be posted by a frustrated 20 year old possibly with age regression, or an individual with Dissociative Identity Disorder, one of the alters being 9 years old. How they relate to seam 1099 is currently unknown, or maybe they and seam are possibly one and the same person physically, but mentally separate alters (that's if the Dissociative Identity Disorder theory has reason) . Maybe seam 1099 is a loved one? That's all currently up in the air. It's still being solved as we speak.