I'm facing the same issue the phone does not recognise the headset, instead is showing as "Charging connected device via USB".
I dont know why Samsung is not solving the issue.
My Notes headphones now dont work suddenly at all when plugged in also the original usb charger is dropping in and out of connectivity, as of 09/01/2021
I took it to a very reputable phone shop to look at it was thouroughly checked for moisture and had the usb port replaced with original parts and tried the port with original Samsung headphones brand new out of a fresh box and still the same problem, was told it is definately a software issue.
I just tried something that seems to have worked.
I had the same symptoms everyone else was reporting: the earbuds would not take over as sound device from the speakers, and messages saying a USB device was connected and then disconnected would appear continuously.
I went into Settings and then Developer Options (these may be hidden), under that there's an option called "Default USB configuration". Under that I selected "Charge phone only". This appeared to correct the problem.
Other choices of default configuration such as USB tethering seem to work too, but charge only seemed safest. I suspect the issue may have occurred because no default was set.
I was experiencing the same problem but I managed to figure out what the problem was. If you go to your settings and you go to your usb-c settings, there you'll find "disable USB audio routing" under developer options. Click right there and once you're in, under media you'll see that the icon is switched on..you have to switch it off and from there your headphones should detect. If they don't, retry everything with your headphones connected and while your music is playing and switch off the icon, it should work.👍🏾
I would like to share my experiance with that. Few days ago it happened to my phone as well - it stopped recognizing AKB earbuds or Dragonfly DAC (it was working fine few days ago for a year). My phone also stopped recognizing USB flash drive. Everything else worked correctly: charging, PC connectivity, DEX via PC, android-auto ... everything which didn't require giving power to additionall device.
I searched a lot for the solution and tried everything I've found: cleared cache, cleaned usb slot and even did factory reset - nothing helped.
I knew my AKG earbuds are OK - connected to a different phone they are working fine.
I've tried 'Samsung Members' app and tested the earbuds - they were not recognized.
Just a moment ago I had a chance to test my earbuds on another Note 10+ and it worked - no big suprise.
But the VERY BIG supprise to me was - that, after I tested that on the other phone - it started to work on mine!!!
Now all is working fine again
Samsung - can you explain what could happened here?
Be interesting to hear the reply from Samsung on that one, my akgs dont work at all and usb charger connectivity is below par, have had parts replaced but still issues remain. Was told software issues.