Mightyjet 538 issue

[bondno9]

I have the pump set to stream mode. I set it to a single speed to keep the water at the same level since I run a ATO. I come home from work and it’s still set to 1.9 but I see the water level consistently changing as if it was in sine wave mode. Luckily my ATO reservoir was low so it didn’t overfill my tank much but man that would’ve been a nasty accident. Anyone have this issue before?

 

[Reefing Madness]