If it's an 8000 and up it's probably the SCV barrels.  Go pick up a couple complete barrels and some o-ring kits.  The one where the hose is popping out may not necessarily be the problem but it's a place to start.  Put in the new ones as needed and rebuild the ones you take out.  Typically on our 8300 we'd end up doing them all over the next week so we started doing them all.  Once that stops working it's time for all new barrels and hose ends.  Hose ends wear out too, but it never seemed to be the main issue.  We would do them when we did new barrels though to get maximum time before any more issues and tips can be used on equipment that stays hooked to older tractors.  Shoup has the barrels cheaper than mother Deere.  If you don't mind the price, replacing them all is the fastest way to sanity.