Not sure if it’s the same issue, but mine makes an occasional faint electric noise (like an old hard drive being read) every once in a while. Not sure if that’s the fan or some other component. I just know my LCD model never did this. It’s not causing any performance issues or stuttering at all though.
I’m just disappointed by how quiet they are on both my LCD and OLED models. It’s not that I NEED the speakers to be obnoxiously loud at max volume, but if you try to play the device in anything but a perfectly quiet room it’s easy for a lot of games to get drowned out by basic ambient noise like a desk fan working.
I swear my LCD one was a little louder when I first got it, but a SteamOS update dropped the max volume down at some point along the way. I tried every single trick posted online by tweaking things in desktop mode but none of them work. Seems like switching back to gaming mode dumps it back into the default settings.
Aside from maybe using a third-party solution I think the only option left is to simply use a pair of wired or Bluetooth headphones/earbuds.