It might be a power supply giving up. Some of them use cheap capacitors that don’t last very long.
You could try running at reduced brightness. If that helps then I’d try adding some bulk capacitors near the power supply output if possible, or replacing it.
If not, try pulling the PB out and powering alone with a different supply like usb. See if it’s stable on its own.
I haven’t switched the power supply yet, but I went through the settings pages, and somehow my LED count had been reset to 0, and the LED type reset to No LEDs. I’ll double check the power supply later (it’s in a hard to access spot.)