Apple TV 3rd gen in password loop

I have called Apple support, stayed on the phone for about an hour. It was fixed for about two days now I have same issue.

I get a message saying my password and or apple ID is incorrect, I entered my PW and followed it with the cide on my phone. I went through this many times to no avail.

Does anyone have any recommendations for a RELIABLE platform to play my music library on my home stereo system? This is totally unacceptable! LONG TIME apple CUSTOMER SOON TO BE GONE!