For two years we had amazing early Raspberries. thought they were supposed to be foolproof! Followed all books to the T. Third year they all turned brown and died after growing and leafing up wonderfully. Waterlogged? We re-dug and put on a mounded rows.(Slightly clay soil.) Year 4 Still not good – some canes grew 12 inches, turned brown and died – some never stared growing. Gooseberries, blueberries, currants all grow wonderfully in same place. Everyone I know calls them weeds, but we can’t get them to grow.
Also, heavy soil pre-disposes the plants to cane blight which is a fungal disease that causes canes to collapse in summer. Cane midge is a possiblity too, with summer dieback in this case too. And the cane blight can sometimes follow the damage done by midge larvae. Check for raised bark, purple discolouration and the presence of small grubs.
Cut away affected canes and burn them and, if there are midge larvae present, spray with an insecticide such as bifenthrin, or physically remove them and distrub the soil in winter to expose them to predators.