You should only plant seeds about 1/4" deep. Because it doesn't have enough energy to fight through that depth of soil.
Don't compact soil. You should sarurate your growing medium befire planting. The water will compact the soil for you. While watering a dry fresh pot of soil watch it as it settles thats all the compacting you need. allow excess water to runout you want the medium moist not soaked.
Are you germinating the seeds in a paper towel or cup of water before planting? While this is not necessary it tells you exactly which seeds are good before planting. Hope this helps & good luck.