Does your company permit manual thrust landings?
I find that all Airbus (Airbii?) Have a tendancy to sometimes give you a wallop of thrust right when you dont want it approaching the flare if using the auto thrust. On the rest of the single aisle types it's not a big deal as the FBW magic takes care of most of it, but on the 321n you're in (effectively) Direct Law for landing. This gives you a pitch - power couple and can destabilise the approach in the last 100' or so.
Other than being alive to the possibility & keeping the engine instruments in your scan, I don't know a good way around it (my company won't allow manual thrust landings in normal operations).