This is my first time here. We own a Caldera Tahitian hot tub, purchased in 2011. We have replaced each jet pump once, and have had wonderful use of our tub. Now, the larger pump with 2 speeds (Pump 2), is turning on mysteriously. It goes on when we use the clean cycle and when we use Jet 1, but only on low. When we try to change the speed to high, it either does nothing or shuts off. You can hear the motor attempt to change gears (it gets louder for less than a second) before it shuts down. Then, in a few minutes, it turns back on to low by itself. One time it tripped the circuit breaker. We've cleaned the filter and added water, but it didn't help. We have been using the hot tub without the benefit of the high pump on Jet 2. Pump 2 was replaced in March of 2013 while still under warranty (for a different reason). Can anyone help us troubleshoot this problem without calling for service or replacing the pump?