Can also be a leak in the fluid line, usually at a fitting, somewhere between the solenoid and the ram. The ram is in the floor of the basement, below the middle plastic strip. Check each fitting union from the solenoid block on the ceiling of the basement to the ram, looking for almost clear, wet area, maybe a small drip evident. That's how I found my living room slide creep source. I believe the solenoid block on the ceiling has all the solenoids for the SBs. Jack & slide solenoids are in the alum. block @ the HWH pump.
Baja-tested '08 2-slide 36'
Alpine: The Ultimate DIY'er Project