Re: USB-C to 3.5mm adapter with Earphones not working (Galaxy Note 10+)
I am putting a summary here to help anyone who may have the issue in the future - the issue has been resolved
The initial problem was as noted in the title of this post
Symptoms that constituted the problem
1. It charges as normal, 2. can connect via HDMI, 3. cannot be connected to the PC (that might just be the because I have a Win7 - not sure), 4. cannot connect to earphones via a USB-c to 3.5mm Jack even though they are both original Samsung accessories. 5. I cannot say whether a USB-C set of earphones works because I don't have any. 6. however, I doubt they would as the USB-c to 3.5mm setup works on my other Samsung phone without any issues. 7. Yet I know the adaptor has not been rejected by the system because I also tried a Huwaei & other USB-C adapter and it said that it was incompatible
In addition, I have noticed that when I use Dex through a hub it will not allow connections other than the HDMI connection and the USB-C power in. This seems to contrast with the experience of other users who can use their USB 2 & 3 along with SD ports.
My Troubleshooting efforts
To date I have followed the 1. Samsung troubleshooting advice on this issue, 2. airbrushed the ports as advised, 3. reset all setting, 4. master reset, 5. used multiple adapters with multiple earphones etc, 6. adjusted a variety of USB settings and audio settings within developer options - ...sound still played from the speakers
How it was resolved
I contacted Samsung repairs and to cut a long story short the repairman said that the port on the phone delivered a limited functionality that would not necessarily be noticed in normal usage - he tested it and it came back as defective - they changed the port and it works as it should now - hope this helps someone