Sometimes it's a sign of too much sand in tee filter too, however, you should NOT get sand into the pool after rinsing if levels are correct.
most lateral issues appear after winter since the filter tends to go through many freeze thaw cycles while sitting out there and any moisture left in there causes expansion and contraction, after numerous years of use, the plastic that the laterals are made from becomes more brittle and thus more susceptible to breaking. Anything over 4 years, I'd guess a lateral went south. Cheap to replace.