Originally Posted by Andy Sager
I've found that most airpumps get noisy from the back pressure. You need to have an extra air outlet in your gang valve or airline to release this pressure. It not only quiets down the pump but it also makes the pump last longer. Anyone hear of a hush 3 airpump? I still have one working and I'm using it still.
Hope this helps
Plus 1 - a cloth mat may also help.