I'll start with what I'm sure of:
1. You don't have a problem with SF, but with ATV+
2. I have never seen this error in my or other people's logs
That's why I can't present a tested solution.
During my first ATV+ DL tests with three programs, I already had
problem with too many streams on the very first day.
This surprised me, as I never had more than one stream open
and all tests were carried out on the same PC with the same IP.
After 24 hours it worked again and 2 days later the same problem.
During further tests, I was able to determine that it was not simultaneous
streams, but the number of trusted devices caused the problem.
After logging in, the query “Trust this device” (or similar) appears.
You must not activate this in too many browsers,
otherwise you will be forced to take a 24 hours break.