Jebao WP10 controller issue

I'm having a weird problem with my wp10 set on W1 mode. It worked just fine, had a nice standing standing wave going but I came home one day and noticed that the pulse length had changed. Instead of turning on/off a couple times a second it was doing very long pulses, maybe 8-10 seconds on/off. Adjusting the dial on the controller has no effect. I had the pump for maybe 2 months before this happened.



This is such a strangely specific issue, I'm wondering if anyone else has seen this? I searched around online and couldn't find any mention of it. Anyone have an idea what caused this? Thanks in advance.