Hello, My Airbank was not holding a charge for more than 2 days. I contacted the manufacturer and they said to leave it on the charger for 24 hours. I did a test run and pumped up 3 wings and a inflatable board. This brought the charge down to 2 bars. I connected it back to the charger and left it overnight. The next day I removed it from the charger and let it sit. I came back about 4 hours later and noticed a faint ticking sound similar to a clock. I opened the unit and noticed the small vent fan was constantly cycling on and off (76 times per minute). I believe this is what is draining the battery over the course of 3 to 4 days. Is there a way to stop this? Thank you.