Candy Dishwasher CD622 – water softner and regeneration

I came across a rather unusual (unusual to me!) fault, I repaired this dishwasher two months back which was a circulation motor seized, then I was called back yesterday (my client assumed my workmanship was to blame) for water leaks under “warranty” repair which turns out that my workmanship was not to blame nor the component in question – thankfully! However, the fault was leaking water during washing cycle, on inspection, I spotted the water leak from the connection points between water softener and regeneration matrix, initially I thought the o ring seals were to blame but doubted very much as there were a lot of water coming out under pressure. I am left wondering if it is viable to replace the o ring seals, or complete replacement of water softener and regeneration matrix otherwise I maybe inclined to condemn the dishwasher. My client says the machine is 9 years old. I understand his concern of not wanting to spend a great deal of cash. Some advice would be good?