I had a similar problem with my Equalizers and it turned out the jacks were undersized right from the factory. American Coach upgraded them to the larger size (at their expense) and all was fine thereafter.
I would think your TS Select came with the biggest size to start with, but who knows? Maybe somebody installed the wrong ones?
Have you called Equalizer to discuss the problem? They were helpful to me.
Former owner of 2004 American Tradition and several other RVs
Home is West Palm Beach, FL