I have a 485 gallon spa with 2 challenger Triton pumps. 1 is a 1 speed boost pump. The other is the primary 2 speed pump, which also pushes the water through the heater. It is always on, either in high speed mode when we use the spa or in low speed mode when it is just circulating. Today, we used the spa for about an hour with all the jets running. Then, when I went to shut it down, the boost pump shut down, but the main pump would not go into low speed mode. I kept pushing the button but it wouldn't switch. There's also a little switch on the back of the motor, but it did nothing when I switched it. I have 4 large round buttons on the side of the spa tub. They are high/low on the main pump, then on/off for the boost pump, on/off for the bubbles, and on/off for the spa light. Is this a problem with the motor or with the button? I am not sure how to remove and service the button if it is a problem with the button. The spa is mounted into a concrete fixture and only removing the shell will give access to what is underneath the spa. The motors are on the side of the house with the pool equipment. It's only pipes underneath the spa. I can post pictures of the buttons if it would help. They're large and round and you have to push down pretty hard to get them to work. The buttons travel about a half an inch or more when I push them down. They've all been working perfectly, until just today. Of course, it could also be an electrical problem somewhere else. I'm just not sure where to start.