Well we're on our (IIRC) 8th problem, and this one happened just this weekend.
Vacuum breaker went out on our dometic toilet. So, we made do by keeping a small bucket nearby...just used that to keep the potty filled and for flushing.
dunno if we'll return the TT for warranty replacement or try to replace it ourselves, depends on what our dealer has to say about scheduling since we're takin 'er out again at Thanksgiving.
We're takin 'er back for some issues in early December anyway; power jack limping along if you tap it with a wrench, one of the crappy day/nite shades has a string failure (we're supporting it up off the floor with command hooks), LP valve *SINGS* constantly when in use, BR slide "wobbles" when being retracted...side to side movement uneven.
It seems lately that every time we take 'er out we add something to the list.
We had to return 'er not long after purchase (June) due to a serious wiring issue (sofa leg falling through a huge wiring hole in the floor, causing wires ...12V *and* 110V... to be pinched and abraded against the ragged hole edge by the leg) on passenger side rear. Others soon reported the same problem in their TTs.
Not exactly a crier, but I'm not doin' a Snoopy Happy Dance either.
Yes, some of these are just luck of the draw issues, but that sloppy hole in the floor (it was cut in the wrong location) was just that; *SLOPPY* don't give a crap workmanship.