I wanted to post this today to potentially help people that end up with weird random behavior from Roon. This morning when I opened my iPad to play some tunes I was presented with the pop up that said Roon could not log me into Tidal. It worked yesterday. No updates were pushed to the core machine or to my iPad. My core runs on a QNAP TVS-471. It has done so since day one five plus years ago. I tried to log into Tidal but the log in kept failing. I set it aside and listened to stored music. I tried again about three hours later and same behavior. So I went into the QNAP interface and stopped and restarted the core. When I restarted Roon on my iPad I noticed that Roon auto logged me into Tidal like always. Problem solved by rebooting the core. Moral to the story? Weird behavior can sometimes be cured with a core reboot. Hope this helps others.