Has it been hot where you are? LOL! Dryness is the most common cause of poor germination. It is always wise to plant some of the seed inside in a flower pot in your house--so you can keep it moist and at a proper temperature. Maybe in a coffee mug on your desk. Also put some in your own yard under irrigation just to be sure.
All seed is tested by law; (and it sort of protects the seed company). You can't sue the testing agency. What was the test date and the germination percent? Was the seed stored under hot conditions?
10 minutes per zone may not be enough if you have hot weather conditions. How much in inches is ten minutes of sprinkling? How much water in inches per week? What is the evapotranspiration calculation in your area this month?