Hidden Radio Flashing LED?

After weird disconnects while using my Hidden Radio, one of the troubleshooting tips is to fully charge the Hidden Radio. So I tried that, and after a few hours (~5) of charging, the LED light started blinking in this repetitive pattern.

I tried a different charger, but the LED continued to blink in the same pattern. Is this normal? Looking through the manual, I didn’t see anything describing this sequence of blinking. I hope it’s nothing…