I opened this thread on December 22 after they stopped working and by Jan 15 I had everything working again. Both the firmware and APP updates fixed it for me.
I’m using the same configs as I was back then (NAS/RTSP, Digest on security), have since updated the firmwares multiple times and didn’t suffer any more downtime or errors with RTSP.
I’m able to use them on the APP, VLC, Frigate,… (I don’t have a Homebase of any kind so I can’t help you there)
I’m also using the 2k Indoor Pan&Tilt. Maybe try reseting the cameras and check your network configs to see if there’s nothing blocking the packets? Don’t really know what else to tell you.